A man who's seen his share of press conferences, he clutched my tape recorder like a microphone, tossing it from hand to hand, sometimes placing it on the table, sometimes millimeters from his lips, all with the dextral arrogance of an athlete playing a home game.
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Asymmetric folds within a dextral sense shear zone, Cap de Creus Asymmetric boudins of pegmatite within a dextral sense shear zone, Cap de Creus Shear bands developed in a dextral sense shear zone, Cap de Creus The sense of shear in a shear zone (dextral, sinistral, reverse or normal) can be deduced by macroscopic structures and by a plethora of microtectonic indicators.
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There is a tectonic inversion at 5 Ma, which initiated the dextral movement of the South China block. However, some researchers don't think that the dextral movement of the South China block reached Yinggehai basin while they argue that the dextral subsidence in the Yinggehai basin since around 5 Ma was resulted from the southeastward roverent of Hainan island.
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Whole body inversion is observed as chiral (dextral, sinistral) coiling in gastropods. While dextral coiling is the most common as it appears in 90-99% of living species, sinistral species still have arisen many times.
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The closest relative of Ayna is probably Clausilioides. A. mienisi is a chirally enantiomorphic species. This means that some specimens have sinistral (left-coiled), others dextral (right-coiled) shells. The sinistral and dextral specimens form "clear" populations but can by found sympatrically as well.
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It is bounded by dextral wrench faults (possible transform faults) and probably represents a pull-apart basin.
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Gasteropod shells may be sinistral or dextral, according as the whorls turn to the left or right.
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In scientific usage a dextral (, right) shell has the opening on the right, when viewed with the spire . The opposite is sinistral (, left). This is consistent with the terms for right-handed screws in engineering and physics. Most species of sea snail are dextral, though some are naturally sinistral.
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There are 22 species in the genus. 17 species have a dextral shell and 5 species are sinistral.
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The shell is carried upside down with the aperture on the right, and this makes it appear to be dextral.
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The shell is carried upside down with the aperture on the right, and this makes it appear to be dextral.
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The shell was carried upside down with the aperture on the right, and this makes it appear to be dextral.
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The shell was carried upside down with the aperture on the right, and this makes it appear to be dextral.
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Gastropods undergo spiral cleavage, a feature commonly seen in lophotrochozoans. As the embryo divides, quartets of cells are oriented at angles to each other. In the snail Lymnaea stagnalis, the direction of rotation during the first cell division signals whether the adult will show dextral or sinistral coiling, At the third cleavage (8-cell stage), spindles in dextral snails are inclined clockwise whereas they are counterclockwise in sinistral snails. Furthermore, injecting L. peregra sinistral eggs with the cytoplasm of dextral eggs before the second polar body formation will reverse the polarity of the sinistral embryos.
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Amphidromus sekincauensis is a species of sinistral or dextral air-breathing tree snail, an arboreal gastropod mollusk in the family Camaenidae.
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Malacologia, v.25, no.1, pp 241-254 Coiling is dextral, although it appears sinistral, deduced from the position of the channel (presumed to be exhalent) contained in a ridge or keel (a selenizone on what is assumed to be the upper side. This is supported by the operculum of Maclurites, which corresponds to that of dextral gastropods.
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Within a normally-dextral species, rare individuals may develop sinistral coiling. In religious usage, the (sacred conch shell) is displayed spire . In this orientation, a common dextral shell has its opening on the left (), and rare sinistral shell has the opening on the right (). For Sanskrit , the Hindi pronunciation is usually written in Latin script as .
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The shell of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral.
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The shell is dextral, and it has 5¾ whorls. The height of the shell is 34.08 mm. The width of the shell is 28.70 mm.
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In a few cases, both left- and right-handed coiling are found in the same population. Sinistral mutants of normally dextral species and dextral mutants of normally sinistral species are rare but well documented occurrences among land snails in general. Populations or species with normally mixed coiling are much rarer, and, so far as is known, are confined, with one exception, to a few genera of arboreal tropical snails. Besides Amphidromus, the Cuban Liguus vittatus (Swainson), Haitian Liguus virgineus (Linnaeus) (family Orthalicidae), some Hawaiian Partulina and many Hawaiian Achatinella (family Achatinellidae), as well as several species of Pacific islands Partula (family Partulidae), are known to have mixed dextral-sinistral populations.
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The Petrified Springs Fault is a right lateral-moving (dextral) geologic fault located in western Nevada, United States. It is considered an integral part of the Walker Lane.
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Some gastropod shells, like those of Partula can coil in sinistral and dextral directions such as these, Neptunea angulata (left) and N. despecta (right) shells. Partula suturalis is polymorphic for shell chirality in that it has two forms: sinistral (left-handed) and dextral (right-handed) shells, unlike other monomorphic species on the island of Mo'orea which have only one form (with the exception of P. otaheitana). This polymorphic trait has a direct effect on mate choice and mating behavior; as shown in laboratory mating tests that opposite-coil pairs mate much less often. In areas where P. suturalis lives sympatrically with other sinistral and dextral Partula species, the opposite P. suturalis morph is typically present.
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New Zealand lies along the boundary between the Australian and Pacific Plates. In South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In North Island the displacement is mainly taken up along the Kermadec subduction zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS). A group of dextral strike-slip structures, known as the Marlborough Fault System, transfer displacement between the mainly transform and convergent type plate boundaries in a complex zone at the northern end of South Island.
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However, the Quaternary movement is believed to be sinistral. Before Miocene time, most of the faults of northern and western Colombia probably had dextral movement.Paris et al., 2000a, p.
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The dextral slip rate for this section is 4.9-7.6 mm/yr, with a single-event displacement of 3.5-5.5 m and a recurrence interval of 500-1120 years.
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Dextral fault movement between the South American and Caribbean plate started 17–15 million years ago. This movement was canalized along a series of strike-slip faults, but these faults alone do not account for all deformation. The northern part of the Dolores-Guayaquil Megashear forms part of the dextral fault systems while in the south the megashear runs along the suture between the accreted tectonic blocks and the rest of South America.
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The spire is conical, its outlines a trifle concave;. It contains 8 whorls. The dextral apex is subimmersed. The first two whorls are quite convex, the following whorls slightly convex.
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The sinistral specimens were described as a species (Ramusculus laevitortus Schütt, 1995) differs from the dextral Ramusculus mienisi. The species inhabits a relatively small area in Erzurum Province, northeastern Turkey.
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The third right arm is hectocotylised in the males, and these have a large ligula which is not laminated. In life, Needham's sac extends into the dextral side of the mantle.
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Younger (< 50 Ma) ENE-striking sinistral faults at least locally accommodated 5–10 km of dextral strike slip by vertical axis rotation. The fault sets merge southward to form the Foggy Dew fault zone where mylonites record oblique dextral-normal slip (down-to-E). Slip is bracketed between 65 and 48 Ma; some occurred after 60 Ma and the zone records the regional transition from approximately 65–58 Ma transpression to approximately 57–45 Ma transtension.
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New Zealand lies along the boundary between the Australian and Pacific plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In the North Island the displacement is mainly taken up along the Kermadec- Tonga subduction zone, although the remaining dextral strike-slip component is accommodated by the North Island Fault System.Mouslopoulou,V., Nicol,A.
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Euhadra senckenbergiana is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Bradybaenidae. This species is found in Japan. The shell of this species is dextral.
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The minute apex is recumbent, spiral, and dextral. The tip is eroded. The inside is scarcely nacreous, the color pattern showing through. This is a shell smaller than Broderipia iridescens, and more convex.
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Tabriz lies within the complex zone of collision between the Arabian Plate and the Eurasian Plate. The main structures accommodating this oblique collision are west-east trending thrust faults and WNW-ESE trending dextral (right lateral) strike-slip faults. The North Tabriz Fault is an active 150 km long dextral strike-slip fault that passes close to the northern edge of Tabriz city. It has two main segments and an estimated overall slip rate of about 7 mm per year.
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In the west, the hanging wall block of Dauki fault meets the non-folded, undeformed, near horizontal sedimentaries of Sylhet trough of Neogene. It is proposed that the Sylhet sediments were deposited in a pull-apart basin in the releasing bend of Dauki fault during the dextral strike slip movement. Thus the net slip for Dauki fault involves a vertical component and a dextral strike slip component (oblique-slip fault).V. Srinivasan (2005), The Dauki fault in Northeast India: Through remote sensing.
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Finely dentate. Depressed. Flattened, as the spire in some snails. Dextral. Right-handed. Digitiform. Finger-like. Dilated. Expanded in all directions, as the aperture of a shell. Dimorphism. With two forms or conditions. Dioecious.
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The Sovanco Fracture Zone is a dextral- slip transform fault running between the Juan de Fuca and Explorer Ridge in the North Pacific Ocean. The fracture zone is 125 km long and 15 km wide.
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The dextral shell is ovate oblong, subcylindrical and slender. Some specimens are more ventricose than other. The shell has six whorls. The color is white or yellow with none to several broad bands of chestnut.
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Amphidromus kruehni is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Camaenidae. This is the only dextral species in the subgenus Syndromus.Chan S.-Y. & Tan S.-K. (2008).
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The sinistral or dextral shell is imperforate, conic-oblong and solid. The shell has 6 whorls. The spire is slightly convexly-conic and the apex subacute. The suture is margined and the whorls are slightly convex.
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The northernmost strand of the western fault set, the Ross Lake fault itself, is a vertical zone of horizontally-lineated mylonite that separates upper-amphibolite-facies rocks of the Cascades crystalline core from sub-greenschist-facies rocks to the east. Some dextral shear and 6–12 km of NE-side down normal slip occurred from 50(?) to post-45 Ma. At Elijah Ridge, the Ross Lake fault steps westward across a gently dipping extensional zone to the Gabriel Peak tectonic belt. This approximately 100 kilometer long, northeast-dipping mylonite zone is dominated by flattening, but kinematic indicators record dextral shear in the north and reverse shear farther south. This transpressional deformation occurred from 65 Ma (and earlier?) to 58 Ma when at least 7–24 km of dextral slip was probably transferred to the eastern faults by ENE-striking shear zones.
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The last activity of the fault has been estimated at around 500 years ago.Paris et al., 2000a, p.28 The fault displays dextral (right-lateral) movement in ramps, displacing older deformational structures and forming an intense cataclasis.
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The dextral shell is ovate and somewhat ventricose with convex whorls margined round the upper shell. The shell has six whorls. The spire is rather short and obtuse at the apex. The columella is callous and twisted.
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New Zealand lies along the boundary between the Australian and Pacific Plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In the North Island the displacement is mainly taken up along the Kermadec subduction zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS).Mouslopoulou, V., Nicol, A., Little, T.A. & Walsh, J.J. (2007).
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Germarium pyriform; germarial bulb dextral, lying diagonally at body midlength, with elongate dorsoventral loop around right intestinal cecum; ootype lying to left of body midline; Mehlis' gland not observed; uterus delicate, banana shaped when empty. Common genital pore ventral, dextral to MCO. Vaginal pore sinistroventral at level of seminal vesicle; vagina with distal vestibule; vaginal sclerite having sclerotized tube with distal recurved and funnel-shaped terminus opening into vestibule; single chamber usually spherical, with thick wall; proximal vaginal canal delicate, leading to seminal receptacle. Seminal receptacle near body midline.
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The periphery is rounded. The nucleus is minute, apparently dextral. The spire contain seven or more whorls. The umbilicus is deep and narrow, with flexuous walls excavated near the carina, which is marginated with an opaque white band.
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The dextral shell is ovate-oblong, spiro-conic, solid, striatulate. The shell is more obsolete toward the apex and with slightly convex whorls. The shell has six whorls. Shell colors are glossy white ornamented with varying brown bands.
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This left-handedness seems to be more common in freshwater and land pulmonates. But still the dextral living species in gastropods seem to account for 99% of the total number.Asami, T. (1993) "Genetic variation of coiling chirality in snails".
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In the eastern Sudbury area the rock is highly crystalline hornblendic gneiss, which apparently dips at a rather low angle toward the southeast. A paleostress analysis of the eastern exposures near Sudbury shows continuing dextral offset during the Penokean orogeny.
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Predation by pareids on dextral (clockwise-coiled or "right handed") snails is thought to favor the evolution of sinistral (counter-clockwise or "left handed") snails in southeast Asia, where 12% of snail species are sinistral (as opposed to 5% worldwide).
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The boundary of the Svecofennian orogen with the Archean "Kola-Karelian orogen" to the northwest is made up by the Luleå-Kuopio suture zone. The dextral South Finland Shear Zone runns across much of southern Finland in a west–east direction.
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The dextral or sinistral shell is ovate-conic, and colored glossy yellow, green, olive or chestnut; often banded with green or chestnut. The shell has 6 whorls. The color pattern is extremely variable. The height of the shell is 19.0 mm.
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The color of the shell is typically a buff gray to light tan. The shell aperture is located on the right side, i.e. the shell of this species is almost always dextral in coiling. Left-handed or sinistral specimens occur rarely.
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New Zealand lies along the boundary between the Indo-Australian Plate and Pacific Plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In the North Island the displacement is mainly taken up along the Hikurangi Subduction Zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS). The earthquake is thought to have occurred on one of the larger thrust faults within the accretionary wedge, at between ca.
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R. flumineus holds itself in a stationary position on a rock in fast-flowing water by means of a "sucker" formed from its two ventral fins. The mouth is slightly asymmetric; dextral fish tend to curve their bodies to the right as they rest while sinistral fish tend to adopt a left-curving posture. The fish are omnivorous, picking edible items of food off the river bed with the side of the mouth, but dextral and sinistral fish have no preference for which side of the mouth they use for this purpose. The breeding season is from June to August.
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Map of the Marlborough Fault System showing location of the Awatere Fault New Zealand lies along the boundary between the Australian and Pacific Plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In the North Island, the displacement is mainly taken up along the Kermadec subduction zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS).Mouslopoulou,V., Nicol,A.
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The Unguía Fault () is an oblique dextral thrust fault in the department of Chocó in northwestern Colombia and continuing offshore Panama in the Caribbean Sea. The fault has a total length of and is arcuate, running along a strike of 356.3 ± 30.
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Shells of Potamopyrgus antipodarum f. carinata (left) and Potamopyrgus antipodarum (right). Scale bar is 0.5 cm. American 10 cent coin, which is 18 mm in diameter. The shell of Potamopyrgus antipodarum is elongated and has dextral coiling, with 7 to 8 whorls.
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The basal lip is straight, very thick, obtuse, crenulate, lirate inside. The columella is arcuate, ending below in a point or tooth. The umbilicus is white within. The young specimens have a minute smooth, rounded, rather elevated dextral nucleus, and bicingulate periphery.
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The genetics of reverse coiling in a rare dextral mutant of another clausiliid, Alinda biplicata (Montagu), has been studied by Degner (1952). The mechanism is the same as in Radix peregra (Müller), with the direction of coiling determined by a simple Mendelian recessive.
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Left: The normally sinistral (left-handed) shell of Neptunea angulata, a species of sea snail (now extinct) found mainly in the Northern Hemisphere. Right: The normally dextral (right-handed) shell of Neptunea despecta, a similar species found mainly in the Southern Hemisphere.
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The Benton Spring fault zone in Nevada, United States The Benton Spring Fault (also known as the Bettles Well fault) is a right lateral-moving (dextral) geologic fault located in western Nevada. It is considered an integral part of the Walker Lane.
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The size of the shell varies between 3 mm and 5 mm. The small, white shell shows a glassy minute apparently dextral nucleus and about six whorls. The first one or two have concave arched transverse ribs. The others are very strongly reticulately sculptured.
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The Guáitara Fault () is a dextral strike-slip fault in the department of Nariño in southwestern Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 044.1 ± 4 in the Western Ranges of the Colombian Andes.
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The Piedrancha Fault () is a dextral oblique strike-slip fault in the department of Nariño in southwestern Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 033.8 ± 14 in the Western Ranges of the Colombian Andes.
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The Vianí Fault () is a dextral oblique thrust fault in the department of Cundinamarca in central Colombia. The fault has a total length of and runs along an average northwest to southeast strike of 055.5 ± 15 in the Eastern Ranges of the Colombian Andes.
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818 It has been suggested that these two realms are dominated by respectively Nazca and Caribbean Plate subduction.Yarce et al., 2014, p.57 The compressional stress regime caused the formation of the oblique sinistral Bucaramanga-Santa Marta Fault and dextral Oca and Boconó Faults.
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Common genital pore ventral, dextral to distal chamber of MCO. Vaginal pore sinistroventral at level of seminal vesicle. Vaginal vestibule delicate; vaginal sclerite with distal funnel and two comparatively large juxtaposed thick-walled chambers; seminal receptacle subspherical, immediately proximal to vagina and anterior to ootype.
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The shell is dextral and relatively thick-walled. The shell is opaque, the surface is matte. The colour is amber on the coast, inland it is rather pale yellowish grey to greenish white in colour. The surface is rough and bears somewhat irregular growth bands.
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The dextral shell is elongate-conic, imperforate with convex whorls and a slightly impressed line below the suture. The shell has five whorls. The color is green with light streaks intermixed. The aperture is subovate and stained with a pink color just within the margin.
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A series of geological faults underlay the gulf. Various of these faults continue across mainland Ecuador. The main faults of the gulf are NNE-SSW oriented and are of mixed strike-slip and reverse type with dextral movement. These faults may generate dangerous earthquakes.
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Relative direction is from the point of view of the observer; a completely symmetrical object has a left side and a right side, from the observer's point of view, if the top and bottom and direction of observation are defined. Chirality, however, is observer-independent: no matter how one looks at a right-hand screw thread, it remains different from a left-hand screw thread. Therefore, a symmetrical object has sinistral and dextral directions arbitrarily defined by the position of the observer, while an asymmetrical object that shows chirality may have sinistral and dextral directions defined by characteristics of the object, regardless of the position of the observer.
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The active tectonics of Ecuador is dominated by the effects of the subduction of the Nazca Plate beneath the South American Plate. The main NNE- SSW trending fault systems show a mixture of dextral (right lateral) strike- slip faulting and reverse faulting. In addition to these faults that run parallel to the Andes in Ecuador, there are two important SW-NE trending- dextral-fault systems: the Pallatanga fault and the Chingual fault. The Pallatanga fault runs close to the epicenter and movement on this fault has been suggested as the cause of the earthquake, although there is no clear surface break supporting such recent movement.
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Testis ovate, lying sinistroposterior to germarium along body midline; proximal vas deferens not observed; seminal vesicle a simple dilation of distal vas deferens, lying posterior to male copulatory organ; ejaculatory bulb and duct not observed; large vesicle (prostatic reservoir?) lying dextral to distal chamber of male copulatory organ. Male copulatory organquadriloculate, with thick walls, short distal cone, elongate tube, protruding filament variable in length. Germarium pyriform; germarial bulb lying diagonally at body midlength, with dorsoventral distal loop around right intestinal cecum; ootype lying to left of body midline, with well-developed Mehlis’ gland; uterus delicate, banana shaped when empty. Common genital pore ventral, dextral to MCO.
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Macluritidae is an extinct family of relatively large, Lower Ordovician to Devonian, macluritacean gastropods(?), hypserstrophically coiled, that is dextral while appearing sinsitral, of which the genus Maclurites is arch- typical. The base of their shells is flat or gently protruding while the upper side is generally concave.
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The shell of this species is dextral (right-handed) in coiling. The shell of an adult snail is 16–27 mm in width. The umbilicus is narrow.Asia and the Pacific Islands - The World of Snails The color of the shell is brown, shading to white underneath.
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The La Plata or Chusma Fault () is a dextral oblique thrust fault in the department of Huila in southwestern Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 039 ± 12 in the Central Ranges of the Colombian Andes.
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The Remolino-El Charco Fault () is a dextral strike-slip fault in the department of Nariño in Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 046.4 ± 6 in the Tumaco Basin along the Pacific Coast of Colombia.
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The Usme Fault () is a dextral oblique normal fault in the department of Cundinamarca in central Colombia. The fault has a total length of and runs along an average north-northeast to south-southwest strike of 022.7 ± 6 in the Eastern Ranges of the Colombian Andes.
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The Totschunda Fault is a major active dextral (right-lateral) continental strike-slip fault in southeastern Alaska. It forms a link between the Denali Fault to the northwest and the Fairweather Fault to the southeast. The northwestern end of the fault ruptured during the 2002 Denali earthquake.
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The rough sinistral (eastern range) or smooth dextral (western range) shell is conically-elongate, solid, slightly rounded, and margined above. The shell has six whorls. The aperture is elongately-ovate and the lip is subreflected. The columella is short, obliquely twisted and has an expanded callus.
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Biomphalaria andecola is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. The shell of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral.
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Biomphalaria peregrina is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. The shell of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral.
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Major active fault zones of New Zealand showing variation in displacement vector of Pacific Plate relative to Australian Plate along the boundary Main active strands of the North Island Fault System The North Island Fault System or North Island Dextral Fault Belt is a set of southwest–northeast trending seismically-active faults in the North Island of New Zealand that carry most of the dextral (right lateral) strike-slip component of the oblique convergence of the Pacific Plate with the Australian Plate. They include the Wairarapa Fault and Wellington Fault to the southwest, the Ruahine and Mohaka Faults in the central section and the Waimana, Waiotahi, Whakatane and Waiohau Faults to the northeast. Most of the fault system consists of dextral strike- slip faults, although towards its northeastern end the trend swings to more S-N trend and the faults become mainly oblique normal in sense as the zone intersects with the Taupo rift zone. This fault zone accommodates up to 10 mm/yr of strike-slip displacement.
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The Argelia Fault () is an inactive dextral oblique thrust fault in the departments of Risaralda and Valle del Cauca in Colombia. The fault has a total length of and runs along an average north to south strike of 014.5 ± 18 in the Western Ranges of the Colombian Andes.
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In the Sims-and-Day model, this last collision in the assembly of the Superior province resulted from northwest-directed tectonic transport of the Minnesota River Valley subprovince terrane against the terrane of the Superior province. The collision was oblique, resulting in dextral-thrust shear along the boundary.
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The dextral shells are mostly of small and rarely medium size. The form of the shell varies from discoidal to turbinate. The round aperture is often modified, sometimes with an incision or a constriction. The last whorl can sometimes be disconnected and then extends strongly from the winding plane.
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Macularia sylvatica is a medium-sized species of air-breathing dextral land snail, a terrestrial pulmonate gastropod mollusc in the family Helicidae. It was once seen as a close relative of the grove snail (Cepaea nemoralis), but does in fact not belong to the genus Cepaea at all .
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The dextral or sinistral shell is ovate-oblong and subventricose. The shell has 6¼ whorls. The shell is similar in form to Achatinella livida, but the spire is less thickened and more pointed at the apex. The color is whitish with chestnut bands, and the apex is pale brown.
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The dextral shell is conic and solid. The shell has six whorls. The glossy color is a uniform white, or ivory yellow with a white sutural line or either of these tints with a burnt sienna band immediately above a wider and darker band. The suture is margined.
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New Zealand lies along the boundary between the Indo- Australian Plate and Pacific Plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In the North Island the displacement is mainly taken up along the Hikurangi Subduction Zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS), which runs from Wellington, up Hawke's Bay and through to Gisborne and the Bay of Plenty. The 1863 earthquake is believed to have occurred outside the Mohaka Fault, just west of Waipukurau.
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A simple example is the coiling direction of any climber plant, which can grow to form either a left- or right-handed helix. Shells of two different species of sea snail: on the left is the normally sinistral (left-handed) shell of Neptunea angulata, on the right is the normally dextral (right-handed) shell of Neptunea despecta In anatomy, chirality is found in the imperfect mirror image symmetry of many kinds of animal bodies. Organisms such as gastropods exhibit chirality in their coiled shells, resulting in an asymmetrical appearance. Over 90% of gastropod species have dextral (right-handed) shells in their coiling, but a small minority of species and genera are virtually always sinistral (left- handed).
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The Naya-Micay Fault () is a dextral oblique thrust fault in the departments of Cauca and Valle del Cauca in Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 034.1 ± 12 in the Tumaco Basin along the Pacific Coast of Colombia.
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The coloration consists of narrow red stripes obliquely descending from the median line to the borders, forming a series of V-shaped markings. The beak is rolled forward and a trifle inclined laterally, but the (dextral) apical whorl is lost. The aperture is oval. Its posterior margin is scarcely expanded.
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The Kanab ambersnail is a terrestrial snail in the family Succineidae. The empty shell is a light amber color. The live snail has a mottled grayish-amber to yellowish-amber colored shell. The shell is dextral (right-handed spiral), thin-walled, with an elevated spire and a Daly, patulous (expanded) aperture.
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The dextral or sinistral shell is conically-elongate, solid, plano-convex and margined above with the suture well impressed. The shell has six whorls. The aperture is subovate and the white lip is expanded, unreflected, somewhat contracted in its center and thickened within. The short columella is flat and lightly toothed.
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The west segment of the Marikina Valley Fault System, the West Valley Fault (WVF) cuts through parts of Muntinlupa and moves in a predominantly dextral strike-slip motion. The West Valley Fault is capable of producing large scale earthquakes on its active phases with a magnitude of 7 or higher.
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The Death Valley Fault Zone (DVFZ) is a right lateral-moving (dextral) geologic fault in eastern California. It runs from a connection with the Furnace Creek Fault Zone in the Amargosa Valley southward to a junction with the Garlock Fault. It is considered an integral part of the Walker Lane.
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The El Tambor Fault () is an inactive dextral oblique thrust fault in the departments of Cauca and Valle del Cauca in Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 026.1 ± 09 to the west of the Western Ranges of the Colombian Andes.
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La Dina Fault () is a regional dextral oblique thrust fault in the departments of Huila and Tolima in southwestern Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 032.9 ± 13 in the Upper Magdalena Valley and the Central Ranges of the Colombian Andes.
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The fault zone is characterized by fault scarps, saddles, linear ridges, displaced streams, shutter ridges, and aligned springs. Some topographic features show evidence of sinistral offset. Locally, two fault traces bound a depressed block (pull- apart basin). Based on stratigraphic evidence, dextral movement of about is reported, which probably occurred before Quaternary time.
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These grabens are linked by a system of North-South orientation faults (sometimes West-East) with dextral cavities that are responsible for most of the earthquakes that can affect the archipelago. The islands themselves are made up of limestone rocks from the Oligocene and Miocene geological epochs, belonging to the Cenozoic era.
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Biomphalaria havanensis, common name the ghost rams-horn, is a species of air- breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. The shell of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral.
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This image "flipping" results in a normal dextral gastropod appearing to be a rare or abnormal sinistral one. Sinistrality arose independently 19 times among marine gastropods since the start of the Cenozoic.Geerat Vermeij (2002). "The Geography of Evolutionary Opportunity: Hypothesis and Two Cases in Gastropods". Integrative and Comparative Biology 42(5): 9359–40. .
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The color of the body of the animal in this species is pale gray. The shells of adult snails are 18–22 mm in width and 8 mm in height. The shell of Triodopsis platysayoides is thin, right coiled (or dextral), and translucent, with 5 whorls. It is extremely flattened in shape.
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Butlin succinctly describes one example of this unique pattern: > P. suturalis is sympatric with the dextral P. aurantia and sinistral P. > olympia, whose ranges abut but do not overlap; P. suturalis is sinestral in > the range of P. aurantia and dextral in the range of P. olympia and does not > normally hybridize with either species. However, where their ranges meet > there is a sharp transition in the coil of P. suturalis and in this > transition zone it hybridizes with both P. aurantia and P. olympia. The reversal in chirality to sinistrality must have evolved as an isolating mechanism, with patterns of reproductive character displacement suggesting speciation by reinforcement. Satsuma largillierti lives on the western half of Okinawa Island while Satsuma eucosmia lives on the eastern half.
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The current tectonics of northern California are mainly controlled by the San Andreas Fault system, the zone of dextral strike-slip faulting that accommodates displacement between the North American Plate and the Pacific Plate along this transform boundary. In addition to the San Andreas Fault itself there are numerous other sub-parallel dextral strike-slip faults that take up some of the plate boundary motion distributed through a zone more than 100 km wide. The 1969 earthquakes and most of their aftershocks occurred along the Healdsburg Fault, which lies between the Maacama Fault and the Rodgers Creek Fault, linked to them by right step-overs. These faults form a continuation of the Hayward Fault Zone north of San Francisco Bay.
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New Zealand lies along the boundary between the Indo- Australian Plate and Pacific Plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. In the North Island the displacement is mainly taken up along the Hikurangi Subduction Zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS). The focal mechanism of the earthquake, its depth and the distribution of aftershocks show that it was a result of oblique normal faulting within the upper part of the subducting Pacific Plate, with the rupture terminating upwards at the plate interface.
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The plate interface above the subducted part of the ridge has a shallower dip than the area to both north and south, the boundaries interpreted to consist of two large tears in the downgoing Nazca Plate. The northern part of Ecuador overlies the subducted part of the Carnegie Ridge and is an area where the Nazca Plate is interpreted to be strongly coupled to the South American Plate, causing an unusually large degree of intraplate deformation. The main active fault zones of Ecuador are SSW-NNE trending dextral strike-slip faults running parallel to the main subdivisions of the Andes, two major SW-NE dextral strike-slip zones, the Pallatanga and Chingual faults, and north-south trending reverse faults such as the Quito fault.
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All three come from the Middle Devonian of N Am, specifically New York, Ohio, and Wisconsin. Differences lie primarily in the symmetry of the whorl section and in the suture. Naedyceras is described as having a loosely coiled low-spired coiled dextral torticonoc. or trochoidal, shell with a flattened dorsum and subtriangular whorl section.
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The Piendamó Fault () is an oblique dextral strike-slip fault in the department of Cauca in southwestern Colombia. The fault is part of the megaregional Romeral Fault System and has a total length of and runs along a variable average north to south strike of 341.6 ± 18 in the Central Ranges of the Colombian Andes.
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The Cucuana Fault () is a dextral strike-slip fault in the departments of Tolima and Cundinamarca in Colombia. The fault has a total length of and runs along an average east-northeast to west-southwest strike of 067.9 ± 6 crossing the Middle Magdalena Valley from the Central towards the Eastern Ranges of the Colombian Andes.
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The Espíritu Santo Fault () is a dextral oblique strike-slip fault in the department of Antioquia in northwestern Colombia. The fault has a total length of and runs along an average northeast to southwest strike of 033.9 ± 5 in the Central Ranges of the Colombian Andes. Estimated activity took place around 500 years ago.
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The Garrapatas Fault (Zone) () is an inactive dextral oblique thrust fault in the departments of Chocó and Valle del Cauca in Colombia. The fault has a total length of and is crescent-shaped, running along an average east- northeast to west-southwest strike of 060.8 ± 14 in the Western Ranges of the Colombian Andes.
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It is a dextral (right- lateral) strike-slip fault with variable amounts of vertical movement causing uplift to the northwest, as expressed by a series of ranges. It forms part of the North Island Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate.
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Left Is All Right; Everything from staircases to scissors gives the advantage to the dextral. So in a world designed with the right hand in mind, why is it that so many lefties are great athletes?, Sports Illustrated, March 9, 2005. He attended Granby High School and quickly became a star on the basketball team.
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6 The bounding fault to the south, the dextral Cuisa Fault with a lateral displacement of ,Hernández Pardo et al., 2009, p.66 has an extension of approximately along a roughly east–west axis and the fault continues to the east underneath the Gulf of Venezuela. The fault is partly covered by Oligocene sediments.
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Tectonic map of Alaska and northwestern Canada showing main faults and historic earthquakes Denali Fault and the Denali National Park boundary The Denali Fault is a major intracontinental dextral (right lateral) strike-slip fault in western North America, extending from northwestern British Columbia, Canada to the central region of the U.S. state of Alaska.
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This is a diaphanous-related formin gene involved in cytoskeleton formation. Dextral embryos treated with drugs that inhibited formin activity phenocopied the sinistral condition. Concurrent work from Kuroda et al. (2016) identified the same Lsdia2 gene (called Lsdia1 in their study) but failed to reproduce the formin inhibition results in the Davison et al. study.
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Aethoceras is a genus of Tarphycerida nautiloids included in the family Estonioceratidae for which the shell is a loosely coiled, gradually expanding dextral torticone with a slightly depressed whorl section. Siphuncle small, ventral, submarginal. Whorl section somewhat resembles early stages of Estonioceras in being laterally fanged. Trochoidal coiling brings to mind the later Trocholitidae.
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Skull of Pareas iwasakii Iwasaki's snail-eater snake (Pareas iwasakii) is a snail-eating specialist; even newly hatched individuals feed on snails. It has asymmetric jaws, which facilitates feeding on snails with dextral (clockwise coiled) shells. A consequence of this asymmetry is that this snake is much less adept at preying on sinistral (counterclockwise coiled) snails.
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Snail-eater in action Skull of Pareas iwasakii Pareas iwasakii is a snail-eating specialist; even newly hatched individuals feed on snails. It has asymmetric jaws, which facilitates feeding on snails with dextral (clockwise coiled) shells. A consequence of this asymmetry is that Pareas iwasakii is much less adept at preying on sinistral (counterclockwise coiled) snails.
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The simplified analogue modelling setting of shear deformation. This model is built on two separate horizontal plates. The brownish layers are dry sand, wet clay, and viscous materials, such as silicone or polydimethylsiloxane. Strike-slip tectonics differ from the dominantly vertical crust movements associated with shortening and extension, being dominantly horizontal in character (in relative terms sinistral or dextral).
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The zone also accommodated dextral shear that resulted from the west–east extension. With the exception of the allochthon Austroalpine material, this thrust evolved at the boundary of the Adriatic and European plates. The central zones of the Alps rose and were subsequently eroded. Tectonic windows and domes as the Hohe Tauern window were formed in this way.
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The Hope Fault is an active dextral (right lateral) strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone.
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Geology of a Transpressional Orogen Developed During Ridge-Trench ... - Google Books. Books.google.ca. Retrieved on 2013-07-21. This started a period of mountain building that affected much of western North America called the Laramide orogeny. In particular a large area of dextral transpression and southwest-directed thrust faulting was active from 75 to 66 million years ago.
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A group of dextral strike- slip structures, known as the Marlborough Fault System, transfer displacement between the mainly transform and convergent type plate boundaries in a complex zone at the northern end of the South Island.Van Dissen, R. & Yeats, R.S. (1991). "Hope Fault, Jordan Thrust, and uplift of the Seaward Kaikoura Range, New Zealand". Geology, 19, 393–396.
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Strong earthquakes can occur along a fault. The San Andreas Fault in California is an example of a transform boundary exhibiting dextral motion. # Plate boundary zones occur where the effects of the interactions are unclear, and the boundaries, usually occurring along a broad belt, are not well defined and may show various types of movements in different episodes.
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These data show that chirality is heritable and maternally deposited in Lymnaea. Several studies have begun to investigate the molecular basis of this inheritance. Nodal and Pitx2 are expressed on different sides of the L. stagnalis embryo depending on its chirality – right for dextral, left for sinistral. Downstream of Nodal, decapentaplegic (dpp), shows the same expression pattern.
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Neoplanorbis is a genus of small, freshwater, air-breathing snails. They are aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails. Neoplanorbis is the type genus of the subfamily Neoplanorbinae. The shells of species in this genus appear to be dextral in coiling, but as is the case in all planorbids, the shell is actually sinistral.
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The shell is dextral and globose- conic.Hamilton-Bruce R. J., Smith B. J. & Gowlett-Holmes K. L. (2002). "Descriptions of a new genus and two new species of viviparid snails (Mollusca: Gastropoda: Viviparidae) from the Early Cretaceous (middle-late Albian) Griman Creek Formation of Lightning Ridge, northern New South Wales". Records of the South Australian Museum 35: 193–203.
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The earthquake occurred on a steeply- dipping fault striking nearly east-west. The focal mechanism shows mainly dextral (right lateral) strike-slip faulting. The magnitude and number of the recorded foreshocks and aftershocks were unusually small, considering the size of the mainshock. This earthquake is the only damaging event in the epicentral area in historical records.
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Eubostrychoceras is a genus of helically wound, corkscrew form, heteromorph ammonite which lived during the Upper Cretaceous (M Turonian - Campanian). The genus is included in the ancycleratid family Nostoceratidae. The shell of Eubostrychoceras is a loosely to tightly wound spiral forming a corkscrew with an open, empty umbilicus in the middle. coiling is commonly dextral (right hand).
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The Rhone-Simplon line is a large geologic faultzone in the Swiss Alps. The line runs from the Ossola valley over the Simplon Pass and then follows the Rhône valley in an east-west direction. Somewhere south of Sion it goes over smoothly into the Penninic thrustfront. Geologically speaking, the line serves as a huge dextral strike-slip fault.
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Ophiolite obduction by the above proposed mechanism would not be expected as the two plates share a dextral transform boundary. However, the major collision of the Kula/Pacific plate with the Alaskan/Aleutian resulted in the initiation of subduction of the Pacific plate beneath Alaska, with no sign of either obduction or indeed any major manifestation of a ridge being “swallowed”.
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The Buesaco-Aranda Fault () is a dextral strike-slip fault in the department of Nariño in southwestern Colombia. The fault has a total length of and runs along an average northeast to southwest strike in the Central Ranges of the Colombian Andes. The 1995 Pasto earthquake is associated with the active fault showing high amounts of displacement. The earthquake caused seven fatalities.
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It may also be simply called a "chank" or conch. The more common form of this shell is known as "right-turning" in a religious context, although scientists would call it "dextral". A very rarely encountered form has reverse coiling which is called "left-turning" in a religious context, but is known as "sinistral" or left-coiling in a scientific context.
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Typical example of dextral shear foliation in an L-S tectonite, with pencil pointing in direction of shear sense. Note the sinusoidal nature of the shear foliation. During the initiation of shearing, a penetrative planar foliation is first formed within the rock mass. This manifests as realignment of textural features, growth and realignment of micas and growth of new minerals.
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Range: Bawean Island, Java. This weakly characterized race differs primarily by its intense color, strong color zone, and slight white margin at the suture. Of seventeen shells collected in May, 1954, by Hoogerwerf at Telaga Kastoba, Bawean Island, ten were dextral and seven sinistral. Three lacked a varix, one was grass green in color, three were whitish, and thirteen had yellow ground color.
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The surface is lusterless, with scarcely visible growth striae. The shell is opaque-white, radiately striped with olive- bordered red lines, generally interrupted and forming a tessellated white and dark pattern. The apex is minute, recumbent, spiral, dextral. The inside of the shell is brilliantly iridescent, not showing the color pattern clearly except at the red-and-white spotted margins.
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Movement is sinistral (left- handed) if the block on the other side of the fault moves to the left, or if straddling the fault the left side moves toward the observer. Movement is dextral (right-handed) if the block on the other side of the fault moves to the right, or if straddling the fault the right side moves toward the observer.
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The shell of this exceeding small (2–4 mm) Valvata species is very flat in its coiling, and therefore it somewhat resembles a Planorbis shell. However, the shell is dextral in coiling and has an operculum.Janus, Horst (1965). ‘’The young specialist looks at land and freshwater molluscs’’, Burke, London The shell is transparent, has 3-3.5 whorls in a circular aperture.
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The length of the shell attains 6 mm, its diameter 2.4 mm. (Original description) The milk white shell contains 6 whorls. The 2½ whorls of the protoconch are dextral, forming a low apex. The first whorl is small and smooth, the second much larger, marked by very slender riblets and fine spiral lirations which increase in strength with the growth of the whorls.
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Benson described the shell of Carinaria galea in detail as "Shell dextral, with the last whorl incurved, compressed, conical, nearly embracing the terminal spire, marked with transverse rugae, broadly keeled. Keel with very oblique rugae, which are curved upwards in the direction of the spire. Aperture transverse, ovate, narrowed towards the keel." It is a large snail reaching a total body length of .
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Genus Achatinella Swainson, 1828: The dextral or sinistral shell is imperforate or minutely perforate, oblong, ovate or globose-conic; smooth or longitudinally corrugated, with only weak traces of spiral sculpture. Shell color is in spiral bands or streaks in the direction of the growth lines. The lip is simple or thickened within and sometimes slightly expanding. The columella bears a strong callous fold.
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Knobbed whelk shells Busycon carica ssp. eliceans The shell of most knobbed whelks is dextral, meaning that it is right-handed. If the shell is held in front of the viewer, with the spiral end up and the opening facing the viewer, the opening will be on the animal's right side. The shell is thick and strong and has six clockwise coils.
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The northeast-oriented Giudicárie line off-sets the (east-west) Periadriatic Seam by 100 kilometers. The fault zone contains older (Tertiary) mylonites, showing it was a ductile shearzone in that period. These mylonites have been overprinted by brittle thrusting still active today. The northwest dipping fault plane serves as a dextral transform fault as well as a compressive thrust fault.
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The shell has seven or eight whorls; the tip of the shell is obtuse, or not sharply pointed. Like most gastropods, individuals typically have dextral (right-handed) shells, though sinistral (left-handed) shells have been documented. Its slime and epiphragms (temporary structures that prevent water loss) are both green. The appearance of the shell is striking and has been compared to painted porcelain.
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Geological Society of London, Special Publication, 290; p. 387–415. A group of dextral strike-slip structures, known as the Marlborough Fault System, transfer displacement between the mainly transform and convergent type plate boundaries in a complex zone at the northern end of South Island.Van Dissen, R. & Yeats, R.S. 1991. Hope Fault, Jordan Thrust, and uplift of the Seaward Kaikoura Range, New Zealand.
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The Irlanda Fault () is a dextral strike-slip fault in the department of Cauca in south-central Colombia. A small portion of the fault runs through Huila. The fault has a total length of and runs along an average northeast to southwest strike of 023 ± 4 in the Central Ranges of the Colombian Andes. The fault is active and associated with the deadly 1994 Páez River earthquake.
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This 42 km long segment runs from near Putara in the south to near Woodville in the north, where the fault branches into the Ruahine and Mohaka Faults. This segment is relatively linear with a strike of 033°. The dextral slip rate for this section is 4.9-6.2 mm/yr, with a single-event displacement of 4.5±1 m and a recurrence interval of 560-1120 years.
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The pale yellow portion shows the Upper Peninsula (UP) of Michigan. Marquette is on the south shore of Lake Superior, straight north of the "'r' in the word 'Upper'". Recent geologic mapping in the Marquette, Michigan, U.S., area provides information of the structure for the zone along a strike. The GLTZ was an active dextral strike-slip zone south of Marquette, passing under the large Marquette anticline.
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Easton is near center. The White River--Naches Fault Zone, at the bottom of the red area, appears to be the southern edge of the OWL. Excerpted from . The Straight Creek Fault (SCF) - just east of Snoqualmie Pass and running nearly due north into Canada - is a major fault notable for considerable identified dextral strike-slip offset (opposite side moving laterally to the right) of at least .
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Map of the Marlborough Fault System The Wairau Fault is an active dextral (right lateral) strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone.
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Map of the Marlborough Fault System The Clarence Fault is an active dextral (right lateral) strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone.
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The Liquiñe-Ofqui Fault is major geological fault that runs a length of roughly in a NNE-SSW orientation and exhibits current seismicity. It is located in the Chilean Northern Patagonian Andes. It is a dextral intra-arc strike-slip fault. Most large stratovolcanoes of the Southern Volcanic Zone of the Andes are aligned by the fault which allows for the movement of magma and hydrothermal fluids.
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Geological Society of London, Special Publication, 290; p. 387–415. The Poulter Fault runs for approximately 50 km Northeast from the junction of the Bealey and Mahinga rivers to the valley of the Hurunui River. Between 16 km and 36 km of the fault ruptured, with dextral displacement of up to 4 metres and dip-slip displacement of 1–2 metres (North side up).
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Cachet Fault is a dextral strike-slip fault in Aysén Region, Chile. The fault runs in north-south direction right to the east of the Northern Patagonian Ice Field. Various west-east glacial valleys have been displaced the movement of the fault. The existence of the fault and its movement has been linked to the Chile Triple Junction and the oblique subduction of Nazca Plate.
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In the Early Miocene ( ) the boundary jumped to its present location which uplifted the Owen Ridge. -long offsets along the OFZ indicate a 3-6 Ma-old dextral strike-slip motion but this motion can be extended to 20 Ma based on magnetic anomaly reconstructions. This coincides with a general reorganisation of continental plates in the Indian Ocean in response to the Arabia-Eurasia collision.
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Sawn sample of the Génis porphyroid showing a dextral shear sense. Below a pronounced angular unconformity one encounters the Génis porphyroid. This rock represents alkaline, rhyolitic ignimbrites (metaignimbrites) of lower Ordovician age (Tremadocian). Its mineralogy is composed of phenocrysts of quartz, alkali feldspar and plagioclase (albite) and a very fine-grained matrix (grain-size 5 μ) made of quartz, feldspars, sericite and rare chlorite.
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Species attributed to the genus Thapsia sensu lato have shell diameters ranging from about 15 to 30 mm, with 5½-6½ whorls. These rather featureless dextral shells are characterized by a low spire and their yellow to brown color. The spiral sculpture of the postembryonic shell is slender. In some larger species the sculpture of the radial ribs is formed crosswise (like the letter X) or beadlike.
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Sinistral and dextral, in some scientific fields, are the two types of chirality ("handedness") or relative direction. The terms are derived from the Latin words for "left" (sinister) and "right" (dexter). Other disciplines use different terms (such as dextro- and laevo-rotary in chemistry, or clockwise and anticlockwise in physics) or simply use left and right (as in anatomy). Relative direction and chirality are distinct concepts.
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Zagreb lies just to the south of the mountain of Medvednica. The northern edge of the mountain is formed by a major southeast–dipping reverse fault that has been active during the Quaternary, the North Medvednica Fault. Earthquakes in this area involve reverse movement on west-southwest–east-northeast trending faults or strike-slip faulting on either northwest–southeast (dextral) or west-southwest–east-northeast (sinistral) faults.
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The Honey Lake Fault Zone in northeastern California The Honey Lake Fault Zone is a right lateral-moving (dextral) geologic fault extends through northwestern Nevada and northeastern California. It is considered an integral part of the Walker Lane. A zone of disturbed landforms reveals the fault's presence on the surface. The geological evidence shows at least four surface- faulting earthquakes have occurred in the late Holocene era.
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The Marikina Valley Fault System, also known as the Valley Fault System (VFS), is a dominantly dextral strike-slip fault system in Luzon, Philippines. It extends from Doña Remedios Trinidad, Bulacan in the north and runs through the provinces of Rizal, and the Metro Manila cities of Quezon, Marikina, Pasig, Makati, Taguig and Muntinlupa, and the provinces of Cavite and Laguna that ends in Canlubang.
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The easternmost part of Turkey lies within the complex zone of continuing continental collision between the Arabian Plate and the Eurasian Plate. The overall shortening that affects this area is accommodated partly by thrusting along the Bitlis-Zagros fold and thrust belt and partly by a mixture of sinistral strike-slip on SW-NE trending faults and dextral strike-slip on NW-SE trending faults. The earthquake was caused by movement on the Çaldıran Fault, one of the dextral faults, which had not been recognised before the earthquake. No earthquakes with magnitudes of 6 or greater were recorded within 100 km of Çaldıran in the preceding 74 years, possibly explaining why it was considered an area of only intermediate seismic risk (zone 3 out of the five zone system of seismic risking used in Turkey at the time, with zone 1 being the highest).
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The Paraíso Fault or Palmira-Buga Fault () is a thrust fault with minor dextral lateral movement in the department of Valle del Cauca in southwestern Colombia. The fault is part of the megaregional Romeral Fault System and has a total length of and runs along an average north-northwest to south-southeast strike of 012.5 ± 3 in the Cauca Basin and the Central Ranges of the Colombian Andes.
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New Zealand lies along the boundary between the Indo-Australian and Pacific Plates. In the South Island most of the relative displacement between these plates is taken up along a single dextral (right lateral) strike-slip fault with a major reverse component, the Alpine Fault. The 1968 Inangahua earthquake occurred along the Northern section of the Alpine Fault, and was considered quite average for what the fault can produce.
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The collision of India with Asia is the latest major tectonic event to affect deformation in the Tian Shan. Thrust faulting is the predominant style of Cenozoic deformation in the Tian Shan, which propagated outward and rose progressively as a wedge-shaped block. Dextral NW-SE trending strike slip faults either merge with or crosscut east-west trending thrust systems. The Talas-Fergana Fault is the longest of these structures.
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The original form of the Orcadian Basin has been modified by a series of later tectonic events. In the late Carboniferous, the basin was partly inverted during dextral reactivation of the Great Glen Fault system. This caused widespread folding and local small-scale thrust faulting. This was followed in the Permo-Triassic and Jurassic by a series of rift events, during which the Inner and Outer Moray Firth basins were formed.
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The coat of arms of the city was adopted in 1954 by the city council. The coat of arms of Saint-Tite is blazoned thus: Greek cross gules a chief azure point, flanked by a toothed wheel segment money dexter and a gear segment sinister gold, containing a skin tight leather gold dextral and sinistral spruce money, overcoming mountains of sand placed on a terrace or charged with a blue river.
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The columella is simple, usually ending anteriorly in a slight tooth.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia The nucleus appears to be either dextral or sinistral indifferently.Dall W. H. 1889. Reports on the results of dredging, under the supervision of Alexander Agassiz, in the Gulf of Mexico (1877–78) and in the Caribbean Sea (1879–80), by the U.S. Coast Survey Steamer "Blake", Lieut.
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In limpets (gastropods without coiled shells) dpp is expressed symmetrically in Patella vulgata and Nipponacmea fuscoviridis. Additionally, in N. fuscoviridis, dpp has been shown to drive cell proliferation Upstream of Nodal, Lsdia1/2 have been implicated in controlling L. stagnalis chirality. Davison et al. (2016) mapped the “chirality locus” to a 0.4 Mb region and determined that Lsdia2 is the likely candidate for determining dextral or sinistral coiling.
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The unit forms part of the Bas Limousin, a basement plateau that was peneplained during the Paleogene. The plateau's elevation oscillates between 300 and 400 meters. Geologically the unit's northern limit is the South Limousin Fault, a very important ductile, dextral wrench fault separating the Génis Unit from the Thiviers-Payzac Unit to the north. To the south the unit is overlain by liassic sediments of the Aquitaine Basin.
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Neoplanorbis tantillus is a species of very small air-breathing freshwater snail, an aquatic gastropod mollusk in the family Planorbidae, the ram's horn snails. This species is endemic to the United States. In 2012, it has been declared extinct by the IUCN Red List of Threatened Species. The shells of this species appear to be dextral in coiling, but as is the case in all planorbids, the shell is actually sinistral.
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Schematic illustration of the two strike-slip fault types. The view is of the Earth's surface from above. In geology, the terms sinistral and dextral refer to the horizontal component of movement of blocks on either side of a fault or the sense of movement within a shear zone. These are terms of relative direction, as the movement of the blocks is described relative to each other when viewed from above.
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After aftershocks from the quake had concluded, examination took place, producing a focal solution to the small events. Movement of these shocks was similar to that of previous earthquakes around the Azores. For these earthquakes, scientists had determined that the conjugate nodal plane was responsible, seeing shearing on the right-lateral (dextral) side. All faulting in this area is strike-slip-oriented, and on a rather large scale.
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The Maacama Fault is a right lateral-moving (dextral) geologic fault located in the Coast Ranges of northwestern California. It is considered to be the northernmost segment of the Hayward Fault subsystem of the San Andreas Fault zone. Creep along the Maacama is about 8 mm per year, consistent with the steady movement along the rest of the Hayward Fault system. It is also capable of producing large earthquakes.
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The tectonics processes in Indonesia formed major structures in Indonesia. The most prominent fault in the west of Indonesia is the Semangko Fault or the Great Sumatran Fault, a dextral strike-slip fault along Sumatra Island (about 1900 km). The formation of this fault zone is related to the subduction zone in the west of Sumatra. Palu-Koro fault is another major structural feature formed in the central part of Indonesia.
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This change apparently had some important ramifications for regional geologic evolution. When this change was completed, Coast Range Arc volcanism returned and sections of the arc were uplifted considerably in latest Cretaceous time. This started a period of mountain building that affected much of western North America called the Laramide orogeny. In particular a large area of dextral transpression and southwest-directed thrust faulting was active from 75 to 66 million years ago.
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The earthquake was estimated to have a magnitude of 6.3 . The ISC-GEM catalogue records it as 6.3 . The focal mechanism shows that the earthquake was a result of strike-slip faulting, either sinistral movement on a NW-SE trending fault or dextral movement on a NE-SW trending fault. As the zone of aftershocks was elongated in a NW-SE direction, the NW-SE plane is regarded as the fault responsible.
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300 px The Wairarapa Fault is an active seismic fault in the southern part of the North Island of New Zealand. It is a dextral (right lateral) strike-slip fault with a component of uplift to the northwest as expressed by the Rimutaka Range. It forms part of the North Island Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate.
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Elimia virginica shells Elimia virginica belongs to the family Pleuroceridae, a group of snails that have thick, elongated shells. The operculum in this species is proteinaceous, corneous, and paucispiral and is withdrawn when the snail is active. The shells are dextral and have a very high and narrow spire, with little space in the suture (the incisions between the whorls). This species has two distinct shell morphologies, one smooth and one lirate (i.e.
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The earthquake was associated with a 50–55 km zone of surface faulting, extending from three kilometres west of Sarikök in the west to just west of Baydoğan in the east. A maximum dextral offset of 3.5 m was recorded. The rupture width was estimated at 24 km and the fault zone was found to dip at 78° to the south. The duration of strong ground shaking is estimated at six seconds.
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The Wagner Basin is bounded on its eastern side by the Wagner Fault, a primarily normal (vertical motion) fault which dips approximately 60 degrees to the northwest. The western side of the basin is bounded by another normal fault, the Consag Fault which dips in a direction opposite the Wagner Fault. The seabed between these faults is sinking. The basin is linked to the dextral (right lateral-moving) Cerro Prieto Fault at its north end.
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Bonanni created the earliest practical illustrated guide for shell collectors, Recreatione dell'occhio e della mente (1681). The two-volume guide was the first treatise devoted entirely to molluscs and included numerous engravings. Bonanni's work is significant for his careful attempts to precisely describe shell morphology. Unfortunately, due to the printing and engraving process, the spirals shown on the shells were reversed from dextral to sinistral, a mirror image problem that later books avoided.
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Lanistes has a unique anatomy among the Ampullariidae: it has a "hyperstrophic" sinistral shell. This means that the body of the snail is dextral (as in all other ampullariids), but the shell appears to be sinistral. However the sinistral appearance stems from the fact that the rotation of the shell as it grows is in an upward direction rather than the usual downward direction."Shell". The apple snail website, accessed 16 May 2011.
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The dextral or sinistral shell is imperforate and pyramidal-conic; solid and glossy with an obtuse apex. The shell has 6.5 whorls. Shell color varies, but is typically green and light greenish-yellow in oblique streaks on the last two whorls, with a faint green peripheral band and a dark chestnut band bordering the suture below. The preceding whorl is yellow with a chestnut band and the three embryonic whorls are pinkish gray.
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Biomphalaria glabrata/Schistosoma mansoni provides a useful model system for investigating the intimate interactions between host and parasite. There is a great deal of information available about this snail, because it has been, and continues to be, under intensive study by many malacologists, parasitologists and other researchers, on account of its medical significance. The shell of this species, like all planorbids, is sinistral in coiling, but it is carried upside down, and thus it appears to be dextral.
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The Ibagué Fault () is a major dextral slightly oblique strike-slip fault in the department of Tolima in central Colombia. The fault has a total length of and runs along an average east-northeast to west-southwest strike of 067.9 ± 11 cross-cutting the Central Ranges of the Colombian Andes. The fault is part of a regional shear zone and has been active in historical times, possibly associated with the 1825 Ibagué earthquake and an earthquake in 1942.
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The player must shoot the enemy aliens and catch the falling scientists. Sometimes the aliens will carry lethal androids instead, which must be avoided. The ranks awarded to players at the end of a game are: # Not Listed - practice recommended # Dextral Dodger # Trekie # Moon Cadet # Planetsman # Ace # Planet Marshal # Planet Lord # Star Warrior # Solar Prodigy # Megastar - mission completed There are 99 levels of gameplay, each increasingly difficult. After level 99, the levels repeat starting level 95.
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The first Georgian flag design came about during the era of the early Georgian state, the Principality of Iberia which had a red cross against a white background, similar to the flag of England. The subsequent Principality of Tao-Klarjeti shared this same flag. The flag of the Kingdom of Abkhazia had 4 green strips in a dextral position on the right side, while the left side contained the cross seen on the current Georgian flag.
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The Waiohau Fault extends from the end of the Ruahine Fault north towards the Bay of Plenty. It lies roughly parallel with, and to the west of, the Whakatane, Waimana, and Waiotahi Faults, and to the east of the Taupo Rift. At its southern end it is a dextral strike-slip fault, becoming a normal dip-slip fault for the northern part of its length. The valley of the Rangitaiki River approximately follows the line of the fault.
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The Gastre Fault Zone (GFZ) is a NW-SE striking dextral Jurassic Gastre Fault System (cf. Rapela & Pankhurst, 1992) in Central Patagonia, Argentina.W. von Gosena and W. Loskeb, 2004. Tectonic history of the Calcatapul Formation, Chubut province, Argentina, and the “Gastre fault system” From a tentative correlation of the fault zone with the similarly NW-SE trend, it was termed ‘Gastre Fault Zone’ or ‘Gastre-Purén Fault Zone’ to the Lanalhue Fault Zone in Chile by early works.
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Paracolpenteron hubbsii is a species of dactylogyrid Monogenean. It is the single species of the genus Paracolpenteron. It is a parasite of the urinary bladder of the maya needlefish Strongylura hubbsi (Belonidae). According to Mendoza-Franco, Caspeta-Mandujano and Ramírez-Martínez, it differs from other dactylogyrid species without a haptoral anchor/bar complex infecting the urinary systems, gills and nasal cavities by the general morphology of hooks, a dextral vaginal opening, and details of the male copulatory organ.
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The abundant evidence of shear zones suggests the Myanmar Central Belt has undergone severe internal deformation. The exposed metamorphic lineation along the belt indicates different motions within the central belt: (1) dextral pull apart geometry trending in a north-northwest direction during Oligocene to early Miocene forming an "en-echelon" pull-apart basin: (2) fault-propagated folds cored in a west-dipping thrust fault in the basin center implies an east-west trending transpressional deformation from Pliocene-Pleistocene onwards.
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Two famous localities for continental pull-apart basins are the Dead Sea and Salton Sea. Pull-apart basins are amenable to research because sediments deposited in the basin provide a timeline of activity along the fault. The Salton Trough is an active pull-apart located in a step-over between the dextral San Andreas Fault and the Imperial Fault.Brothers, D. S., N. W. Driscoll, G. M. Kent, A. J. Harding, J. M. Babcock, and R. L. Baskin.
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The Walker Lane deformation belt accommodates nearly 12 mm/yr of dextral shear between the Sierra Nevada- Great Valley Block and North America. The belt is characterized by the northwest-striking trans-current faults and co-evolutionary dip-slip faults formed as result of a spatially segregated displacement field.Dokka, R.K., and Travis, C.J., 1990, Role of the eastern California shear zone in accommodating Pacific-North American plate motion: Geophysical Research Letters, v. 17, p. 1323-1326.
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Modern studies have focused on better understanding the evolutionary relationships within the group, as well as solving taxonomic problems. The genus Amphidromus is unusual in that it includes species that have dextral shell-coiling and species that have sinistral shell-coiling. In addition, some species within this genus are particularly notable because their populations simultaneously include individuals with left-handed and right-handed shell-coiling. This is an extremely rare phenomenon, and very interesting to biologists.
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The Rivera Transform Fault, also referred to as the Rivera Fracture Zone, is a right lateral-moving (dextral) transform fault which lies along the seafloor of the Pacific Ocean off the west coast of Mexico just south of the mouth of the Gulf of California. It runs between two segments of the East Pacific Rise, forming the southwest boundary of the small Rivera Plate. The fault is broken into two segments, bisected by a short rifting zone.
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Spawns of small eggs are laid as submerged clumps either directly within the water or attached to submerged vegetation. Eggs are black at the animal pole and cream at the vegetal. Tadpole appearance is the same as the Eastern sign-bearing froglet and Common eastern froglet: dark brown in colour, a dextral anal opening, sinistral spiracle, blunt tail, labial papillar row interrupted on anterior and posterior portions, and a labial tooth row pattern of I, 1/1, II.
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Dextral sense shear folds in mylonites within a shear zone, Cap de Creus Shear zones that approximate to simple shear typically contain minor asymmetric folds, with the direction of overturning consistent with the overall shear sense. Some of these folds have highly curved hinge-lines and are referred to as sheath folds. Folds in shear zones can be inherited, formed due to the orientation of pre-shearing layering or formed due to instability within the shear flow.
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The Kaikoura Orogeny is a New Zealand orogeny that has given birth to the Southern Alps. It began 25 million years ago along the Alpine Fault. In this orogeny, the Southern Alps are being formed because the Pacific Plate is colliding with the Australian Plate, with a predominant oblique dextral motion, but a minor component of thrust faulting. As the plates collide, the crust thickens, with deformation and associated uplift due to isostacy occurring primarily within the Pacific Plate.
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Janua pagenstecheri is a species of marine polychaete. It is widely distributed around the British Isles and across north-western Europe, and has been described as "probably the commonest spirorbid in the world". Janua pagenstecheri lives attached to substrates such as seaweeds including Corallina officinalis, rocks, stones, shells, and the carapaces of crabs. J. pagenstecheri inhabits a shell made of calcium carbonate in the form of a dextral spiral, with the tube up to 2 mm in diameter.
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Biomphalaria straminea is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. This snail is a medically important pest, because an intermediate host for the parasite Schistosoma mansoni and a vector of schistosomiasis. The history of these discoveries was summarized by Paraense (2001). The shell of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral.
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New Zealand lies along the boundary between the Indo-Australian and Pacific Plates. In the North Island the displacement is mainly taken up along the Hikurangi Subduction Zone, although the remaining dextral strike-slip component of the relative plate motion is accommodated by the North Island Fault System (NIFS). Both earthquakes are believed to have occurred along the Hikurangi Subduction Zone, in close proximity to each other. Both earthquakes generated tsunami, caused by the sudden release of energy from the Earth's crust.
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The figure shows the location of plates around Myanmar. Myanmar is traced in dotted red lines, where the strike slip fault is the Sagaing fault and the thrust fault is the Kabaw fault. Modified with Alam et al. (2003) The tectonic setting of Myanmar consists of a highly oblique convergence on the western boundary, a dextral (right lateral) strike-slip fault in the centre of Myanmar defining the Burma-Sunda boundary and the spreading of Andaman Sea Ridge in the south.
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The Upper Rhine Graben extends from the northern edge of the Jura mountains in the south up to the triple junction where the ECRIS branches. Rifting initiated here in the Oligocene but the northern and southern parts of the graben show distinct post-Oligocene histories. In the Miocene the southern part of the graben became uplifted, while the northern part continued to subside into the Pleistocene. Currently the Upper Rhine Graben is thought to be experiencing dextral strike-slip reactivation.
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The basin is structurally bounded by the Palestina Fault, a dextral strike-slip fault system, in the west and the Bucaramanga-Santa Marta Fault, a sinistral strike-slip system, in the east. The major surface structures of the Middle Magdalena Basin are asymmetric synclines and basement cored anticlines, which formed as a result of thrusting from the Eastern and Central Ranges. The thrusting initiated faulting in the Pre-Mesozoic basement. The faults then pushed through the Jurassic layers to the Cretaceous ductile stratigraphy.
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The Hormuz Formation is known from a wide area of the Zagros Mountains and around and beneath the Persian Gulf. Two main depositional basins have been recognised, the North Gulf and South Gulf Basins, separated by the Qatar Arch. The basins were formed as a result of extensional tectonics towards the end of the Pan-African Orogeny. The main structure formed during this period were NW- SE trending dextral (right lateral) strike-slip faults and NE-SW trending extensional faults.
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This damage causes impaired performance on object recognition tasks with a variety of visual stimuli, including colours, familiar objects, and new shapes. This performance deficit is not a result of source monitoring errors, and accurate performance on recall tasks indicates that the information has been encoded. Damage to the posterior parietal lobe therefore does not cause global memory retrieval errors, only errors on recognition tasks. Lateral parietal cortex damage (either dextral or sinistral) impairs performance on recognition memory tasks, but does not affect source memories.
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On extensional duplexes, normal faults will accommodate the vertical motion, creating negative relief. Similarly, left stepping at a dextral fault generates contractional bends; shortening the step overs which is displayed by local reverse faults, push-up zones, and folds. On contractional duplex structures, thrust faults will accommodate vertical displacement rather than being folded, as the uplifting process is more energy efficient. Strike slip duplexes are passive structures; they form as a response to displacement of the bounding fault rather than by the stresses from plate motion.
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Map of the Marlborough Fault System The Awatere Fault is an active dextral (right lateral) strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone. The 1848 Marlborough earthquake was caused by rupture of the whole of the eastern section of the Awatere Fault.
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Symmetry breaking and the evolution of development. Science, 306(5697), 828-833 LR asymmetry is pervasive throughout metazoans and present throughout every major lineage. Notable examples include the large and small claws of the fiddler crab, the left offset of the vertebrate heart, asymmetrical gut coiling in Drosophila melanogaster, and dextral (clockwise) and sinistral (counterclockwise) coiling of gastropods. This asymmetry can be restricted to a specific organ or feature, as in the crab claws, or be expressed throughout the entire body as in snails.
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Oahu tree snails, genus Achatinella, form a large genus of colorful, tropical, tree-living, air-breathing, land snails, arboreal pulmonate gastropod mollusks in the family Achatinellidae. This genus of tree snails is endemic to Hawaii, and all extant species are endangered. They were once abundant and were mentioned extensively in Hawaiian folklore and songs, and their shells were used in lei and other ornaments. Many of these arboreal snails are sinistral or left-handed in their spiral shell coiling, whereas most gastropod shells are dextral.
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A very few species (for example Amphidromus perversus) show an equal mixture of dextral and sinistral individuals. In humans, chirality (also referred to as handedness or laterality) is an attribute of humans defined by their unequal distribution of fine motor skill between the left and right hands. An individual who is more dexterous with the right hand is called right-handed, and one who is more skilled with the left is said to be left- handed. Chirality is also seen in the study of facial asymmetry.
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Pegmatite dyke offset by a steeply-dipping dextral shear zone, Cap de Creus dolomites of the Noonday Formation in Mosaic Canyon, Death Valley A shear zone is a very important structural discontinuity surface in the Earth's crust and upper mantle. It forms as a response to inhomogeneous deformation partitioning strain into planar or curviplanar high-strain zones. Intervening (crustal) blocks stay relatively unaffected by the deformation. Due to the shearing motion of the surrounding more rigid medium, a rotational, non co- axial component can be induced in the shear zone.
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The earthquake was recorded as 6.8 by ANSS and 6.9 by PHIVOLCS. The maximum felt intensity was given as VII MMI on the ANSS ShakeMap and VII PEIS in the PHIVOLCS summary for this event. The focal mechanism indicates strike-slip faulting with either sinistral movement on a NW-SE trending fault or dextral movement on a SW-NE trending fault, but the distribution of the aftershocks are consistent with the sinistral fault plane. The earthquake may be the result of movement on the Tangbulan Fault, according to PHIVOLCS.
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Reconstruction of paleostress requires large amount of data to attain accuracy, so it is essential to organize the data in comprehensible format prior to any analysis. 1) Fault population geometry shown in a rose diagram :1) Fault Population Geometry Attitude of fault planes and slickensides is plotted on rose diagrams, such that the geometry is visible. This is particularly useful when the sample size is enormous, it provides the full picture of the region of interest. 2) Fault movement: components of normal, reverse, sinistral (left-lateral) and dextral (right-lateral) are resolved.
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Benjamin Bley de Brito Neves, Mário da Costa Campos Neto and Reinhardt Adolfo Fuck. 1999. From Rodinia to Western Gondwana: An approach to the Brasiliano-Pan African Cycle and orogenic collage The eastern part of the Uruguayan shield region is crossed by two major shear zones both running roughly in north-south direction the dextral Sarandí del Yí-Piriápolis Shear Zone and the sinistral Sierra Ballena Shear Zone. West of Sarandí del Yí Shear Zone the Río de la Plata Craton is intruded by the Late Paleoproterozoic Florida dyke swarm.
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The Rosas-Julumito Fault () is an oblique dextral strike-slip fault in the department of Cauca in southwestern Colombia. The fault is part of the megaregional Romeral Fault System and has a total length of and runs along an average northeast to southwest strike of 026.9 ± 7 in the Central Ranges of the Colombian Andes. The fault is associated with the 1983 Popayán earthquake that partially destroyed Popayán, the capital of Cauca, and led to more than 300 fatalities. A maximum moment magnitude earthquake of 6.8 is estimated for the fault.
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The Garrapatas Fault runs between the axis of the Western Ranges of the Colombian Andes and the Serranía de Los Paraguas, to the west of the city of Buga. The fault displaces oceanic volcanic and sedimentary rocks and has a very well developed V-shaped valley along the upper parts of the Garrapatas and Las Vueltas Rivers and probably connects with the Argelia Fault. It causes alignment of drainage and parallel streams. Dextral movement in this fault is an exception to the common sinistral (left-lateral) movement of north-south trending faults in the region.
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The Wellington Fault is a dextral strike-slip fault that runs from the Cook Strait on the southern coast of North Island up to near Woodville, where the fault branches into the Mohaka and Ruahine Faults. No historical earthquakes have been recorded along this fault although a significant event is estimated to have occurred within the last 1,000 years. The recurrence interval for large earthquakes on this fault is estimated to be less than 2,000 years. Three main segments have been identified, the Wellington-Hutt section, the Tararua section and the Pahiatua section.
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When a strike-slip fault is offset along strike such as to create a gap i.e. a left-stepping bend on a sinistral fault, a zone of extension or transtension is generated. Such bends are known as releasing bends or extensional stepovers and often form pull-apart basins or rhombochasms. Examples of active pull-apart basins include the Dead Sea, formed at a left- stepping offset of the sinistral sense Dead Sea Transform system, and the Sea of Marmara, formed at a right-stepping offset on the dextral sense North Anatolian Fault system.
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The Denali-Totschunda fault is a major dextral (right lateral) strike-slip system, similar in scale to the San Andreas fault system. In Alaska, moving from east to west, the plate interactions change from a transform boundary between Pacific and North American plates to a collision zone with a microplate, the Yakutat terrane, which is in the process of being accreted to the North American plate, to a destructive boundary along the line of the Aleutian islands. The Denali-Totschunda fault system is one of the structures that accommodate the accretion of the Yakutat terrane.
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When a normal adult dextral shell of this species is viewed ventrally (with the anterior end pointing downwards), the stromboid notch can be observed to the right of the siphonal canal as a shallow, secondary anterior indentation in the lip. The siphonal canal itself is straight, short, and ample; the columella is smooth, without any folds. Adult specimens have a moderately flared, posteriorly protruding outer lip, which is considerably thickened and completely devoid of marginal spikes or plicae. The body whorl is roundly swollen at the shoulder, with a few anterior spiral grooves.
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Downloadable maps available; see , , and . This is suggestive of the OWL being a left lateral (sinistral) strike-slip fault that has distorted and offset the SCF. But that is inconsistent with the SCF itself and most other strike-slip faults associated with the OWL being right lateral (dextral), and incompatible with the geology to the southeast. Particularly, studies of the region to the southeast (in connection with Department of Energy activities at the Hanford Reservation) show no indication of any fault or other structure comparable to the SCF.E.g.
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Map of the Marlborough Fault System Major active fault zones of New Zealand showing variation in displacement vector of Pacific Plate relative to Australian Plate along the boundary The Marlborough Fault System is a set of four large dextral strike-slip faults and other related structures in the northern part of South Island, New Zealand, which transfer displacement between the mainly transform plate boundary of the Alpine fault and the mainly destructive boundary of the Kermadec Trench, and together form the boundary between the Australian and Pacific Plates.
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The Marlborough Fault System consists of four main dominantly strike-slip fault strands, which together carry almost all of the displacement associated with the plate boundary. Other smaller faults form as splays of these main faults or accommodate deformation of the crust between them, such as the Newton and Hura Faults at the western end of the Hope Fault and the Jordan Thrust that formed the Seaward Kaikoura Range. The dextral strike-slip across this zone has also involved clockwise rotation of the intervening fault blocks of about 20° since the early Pliocene.
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Measurements from the southwestern part of the fault suggest 76-80 m of dextral displacement since the Late Pleistocene, about 18,000 years ago. This gives an average slip rate of 3.6-4.4 mm/yr with an average slip of about 5 m for each event. In the northeastern part of the fault, the estimated slip-rate is somewhat higher, 4.7 mm/yr and the average slip also higher at about 7 m. A recurrence interval of about 1500 years has also been estimated for this part of the fault.
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The east-west oriented dextral strike-slip Oca Fault in the north is estimated to have been active since the Early Eocene with a total displacement of . The Bucaramanga- Santa Marta Fault was a Jurassic extensional rift fault, reactivated as oblique reverse fault in the Oligocene.Ayala, 2009, p.11 Petroleum exploration in the Cesar-Ranchería Basin commenced in 1916. The first exploitation of hydrocarbons was performed in 1921 and 1922 at Infantas in the Ranchería Basin and in 1938 the first well (El Paso-1) was drilled in the Cesar Basin.
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Euhadra is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Bradybaenidae. (This snail genus was previously placed in the family Eulotidae). A few of the species in this genus are unusual in that specimens in those species always have left-handed "sinistral" coiling in their shells, as shown in the specimen on the right. The rest of the species in the genus are right-handed or "dextral" in the shell coiling, as is usually the case in the great majority of gastropods.
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In the Triassic at beginning of the Mesozoic as sedimentation continued in the P'yŏngan Supergroup, the Sŏngnim tectonic event affected the Okch'on-T'aebaeksan Zone, although it only caused slight faulting and warping of the major supergroup strata. Geologists have inferred that the event was related to deformation further west in Indonesia. The event generated dextral strike-slip faulting in intermontane troughs in the Kyonggi Massif in which the terrestrial sediments of the Taedong Supergroup accumulated. The rocks in the basin include two sequences of conglomerate grading to sandstone, mudstone and coal beds.
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The active tectonics of Ecuador is dominated by the effects of the subduction of the Nazca Plate beneath the South American Plate. The high degree of coupling across the plate boundary where the Carnegie Ridge is being subducted beneath northern Ecuador causes unusually intense intraplate deformation. Known faults within the area of the earthquake epicenters are the SSW-NNE trending San Isidro, El Ángel, Río Ambi and Otavalo Faults, all considered to be dextral strike-slip faults, sometimes with reverse movement. All these faults are interpreted to have moved in the last 1.6 million years.
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The width of the shell can reach up to 10 mm. In the largest specimen there are almost two teleoconch whorls that initially attach very high onto the protoconch, with the result that the larval shell seems to be embedded rather obliquely within the younger whorls. The diameter of the teleoconch increases rapidly, the result being a shell that strongly resembles Planorbarius (but, of course, dextral). The surface of these younger whorls bears flexuous growth lines, and a dense and very fine, somewhat irregular spiral striation, only visible where light reflects on the shell.
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Shell is dextral, rimate, ovate, thin, smoothish, somewhat glossy, pellucid, brownish- tawny. The shell has 5 to 5 ½ whorls, convex, the last nearly two-fifths the altitude, rounded at base, anteriorly having a somewhat swollen crest. Aperture is slightly oblique, semiovate or piriform, obstructed by 3 teeth: in the middle of the parietal wall, on the columella, and a smaller one in the palate (frequently wanting). Peristome is spreading, slightly labiate, the margins joined by a callus, the right margin very strongly curved above, columellar margin is somewhat dilated, spreading.
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The Furnace Creek Fault Zone in eastern California The Furnace Creek Fault Zone (FCFZ) is a geological fault that is located in Eastern California and southwestern Nevada. The right lateral-moving (dextral) fault extends for some between a connection with the Death Valley Fault Zone in the Amargosa Valley and northward to a termination in the Fish Lake Valley of southwest Nevada. The northern segment of the FCFZ is also referred to as the Fish Lake Valley Fault Zone. The FCFZ is considered an integral part of the Walker Lane.
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The Pyramid Lake Fault Zone in Nevada, United States The Pyramid Lake Fault Zone is an active right lateral-moving (dextral) geologic fault located in western Nevada. It is considered an integral part of the Walker Lane. The fault zone extends to the southeast from Pyramid Lake roughly parallel to the course of the Truckee River between the Truckee Range to the northeast and the Pah Rah Range to the southwest.Anderson, Larry W. and Fred F. Hawkins, Recurrent Holocene strike-slip faulting, Pyramid Lake fault zone, western Nevada, Geology, November 1984, v.
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The Zone is conventionally thought of as representing the dividing line between the Indian Platform with full thickness of continental crust and the Bengal Foredeep. In the south, north–south-trending axial surfaces of folds in Surma basin bend towards northeast while approaching the trace of Dauki fault, indicating dextral strike slip movement along the Dauki fault. This inference is further supported by the outcrop pattern of Haflong thrust in the footwall block with the concavity facing west. This thrust belonging to the BoS abruptly terminates against the younger Dauki fault.
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A contractional duplex that has developed at the bend/stepover along a strike-slip fault. 5830 m high Altun Shan mountains formed at a restraining bend on the sinistral Altyn Tagh fault A fault bend, or fault stepover, forms when individual segments of the fault overlap and link together. The type of structures which form along the strike-slip fault depend on the sense of slip relative to the sense of stepping. When a sinistral fault steps to the right or a dextral fault steps to the left, a restraining bend is formed.
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Like all planorbids, the shell of Biomphalaria glabrata is planispiral, in other words coiled flat like a rope, and the spire of the shell is sunken. Also, like all planorbids, this species has a sinistral shell, in other words, the coiling of the shell is left-handed. However, like all the snails in the subfamily Planobinae, this snail carries its coiled shell upside down, and thus the shell appears to be dextral in coiling. In other families of snails the spire is situated on top of the shell, here what shows on top of the shell is in fact the umbilicus.
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Another encounter point was near what is now Coffs Harbour. These ridge encounters with the trench stopped the subduction at those points and resulted in triple junctions moving north and south up the trench, and being replaced by a dextral transform fault. The northernmost triple junction, a ridge-trench-fault junction moved up the Queensland coast at 28 mm per year. As it moved the magmatism inland stopped and it reached Townsville about 290 Ma. The paired triple junction with this, a fault-trench-fault junction, moved south from Brisbane at about 12 mm per year.
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The Texas-Coffs Harbour megafold resulted from dextral motion (clockwise) along a major fault in eastern Queensland. The hypothetical fault, which is not exposed at the surface was called Gogango- Baryulgil fault zone. 500 km southerly displacement of the coastal terrane which stretches from Coffs Harbour in the south to Broad Sound near St Lawrence, Queensland in the north, brought it into its current position relative to the rest of Australia, and formed a major structural fold inland from Coffs Harbour. The movement may have been caused by absorption of lateral motion between the northern pair of triple junctions.
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The fault system is probably an extension of the Boconó Fault and associated faults of the Mérida Andes in Venezuela and likely continues south as a dextral fault in the Republic of Ecuador. The Eastern Frontal Fault System is the main fault system bounding the Andean Ranges in the west and the lowlands or Llanos Orientales plains in the east. This fault system extends all the way south to the Jambali Graben in the Gulf of Guayaquil in Ecuador. It is considered to be the actual plate boundary of the South American Plate disconnecting it from the North Andes Block.
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145 The fault system is reverse sinistral (left lateral) in the northern part of the country, conspicuous to about latitude 5° N, from there south to Ecuador, it is mainly reverse-dextral (right lateral). The system forms prominent fault lines and well-developed fault scarps as much as high on Pleistocene-aged sedimentary deposits, and eroded scarps on older Cretaceous to Paleozoic rocks. The system forms an outstanding break-in-slope above the easternmost parallel set of faults. The upper part of the easternmost major scarps forms the topographic divide of the Central Ranges of Colombia.
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But at Port Madison (at the red bar in the image) it is split by a distinct offset of several miles. Curiously, the southern section lies in the approximate zone of the OWL. (Note OWL-associated lineaments running parallel to the red line.) This suggests dextral offset along a strike-slip fault. But if that is the case then there should be a major fault in the vicinity of Port Madison and crossing to Seattle (perhaps at the Ship Canal, aligned with the red line) - but for this there is even less evidence than there was for the Puget Sound fault.
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The 20mm/yr dextral (right lateral) strike slip Sagaing Fault detaches the Burma microplate from the Sunda plate. The arc-parallel fault spans over 1400 km in a north-south direction, remarkably linear for the central 700 km (at 17°N to 23°N latitude) and forms a slight arc shape swinging N10°E and N170°E direction at the north and south ends of the fault respectively. Northward, the Sagaing fault terminates at the Jade Mine belt (~ 24.5°N) and splays into a 200 km width compressive horsetail structure. Southward, it is connected to the active Andaman spreading rift.
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The earthquake occurred in a tectonically complex region at the southern edge of the Tien Shan. The southern margin of the Tien Shan is characterised by combination of dextral strike-slip faulting and southward thrusting over the Tajik Basin to the south along the Gissar-Kokshaal fault zone. At the same time the Tajik Basin is being shortened in response to oblique collision with the Pamirs, forming a series of north-south to SW-NE trending thrust faults, the earthquake is thought to have been caused by movement on the Vakhsh thrust, one of these faults.
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Hydrocarbons of the Kapuni Field are trapped by the Kapuni Anticline, in the hanging wall of the east-dipping Manaia Fault, a reverse fault in the Eastern Mobile Belt. The Kapuni Anticline is asymmetric, doubly-plunging, and approximately 18 km long and 8 km wide. The Manaia Fault initially developed as a normal fault bounding the Manaia Graben during Cretaceous to Early Eocene rifting associated with the opening of the Tasman Sea. Dextral transpression associated with the Hikurangi Subduction System caused fault reactivation and basin inversion during the Eocene and Miocene, resulting in the development of the Kapuni Anticline.
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The winter flounder (Pseudopleuronectes americanus), also known as the black back, is a right-eyed ("dextral") flatfish of the family Pleuronectidae. It is native to coastal waters of the western north Atlantic coast, from Labrador, Canada to Georgia, United States, although it is less common south of Delaware Bay. It is the most common near-shore (shallow-water) flounder in the waters from Newfoundland down through Massachusetts Bay, reaching a maximum size around 61 cm in length and 2.25 kg in weight. The species grows larger on Georges Bank, where they can reach a length of 70 cm and weight of 3.6 kg.
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Associated offshore basaltic flows reach as far south as the Falkland Islands and South Africa. Traces of magmatism in both offshore and onshore basins in the central and southern segments have been dated to 147–49 Ma with two peaks between 143 and 121 Ma and 90–60 Ma. In the Falkland segment rifting began with dextral movements between the Patagonia and Colorado sub-plates between the Early Jurassic (190 Ma) and the Early Cretaceous (126.7 Ma). Around 150 Ma sea-floor spreading propagated northward into the southern segment. No later than 130 Ma rifting had reached the Walvis Ridge–Rio Grande Rise.
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The Aegean Sea is an area of mainly extensional tectonics caused by the subduction of the African Plate beneath Aegean Sea Plate. In the northwest Aegean, extension on approximately W-E trending extensional faults is accompanied by dextral (right lateral) strike-slip on SW-NE trending faults, and minor sinistral (left lateral) movement on NW-SE trending faults, accommodating the diffuse plate boundary zone between the Eurasian Plate and the Aegean Sea Plate. The earthquake has been attributed to movement on the Stratoni fault, one of the W-E trending faults that shows predominantly dip-slip extension.
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The San Andreas Fault is a continental transform fault that forms part of the tectonic boundary between the Pacific Plate and the North American Plate. The strike-slip fault is characterized by mainly lateral motion in a dextral sense, where the western (Pacific) plate moves northward relative to the eastern (North American) plate. This fault runs the length of California from the Salton Sea in the south to Cape Mendocino in the north, a distance of about . The maximum observed surface displacement was about 20 feet (6 m); geodetic measurements show displacements of up to 28 feet (8.5 m).
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These horsts and grabens extend from onshore areas northward into a complex offshore terrane that includes the Ionian Sea abyssal plain to the northeast. This plain is underlain by oceanic crust that is being subducted to the north and east beneath the Hellenic arc. The Pelagian province to the west, particularly the pull-apart basins of the Sabratah Basin and extending along the South Cyrenaica Fault Zone (SCFZ) and the Cyrenaica Platform to the east, is strongly influenced by extensional dextral strike-slip faulting. To the south, the Nubian Swell is the stable continental basement for this rifted basin.
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The terrane hosts a swarm of NEE-SSW oriented dykes that date to the Neoproterozoic. East of the SYSZ, the latitudinal Colonia Shear Zone (CSZ) separates the Palaeoproterozoic (2000±100 Ma) Piedra Alta Terrane to the north from the Tandilia Terrane to the south. A period of extensional tectonics in the Late Paleoproterozoic coincided with the formation and intrusion of the Piedra Alta mafic dike swarm and the rapakivi granites of Illescas Batholith. The 1790±5 Ma-old Late Palaeoproterozoic Piedra Alta mafic dike swarm was subsequently affected by the -wide Mesoproterozoic SYSZ and its eastern end bends along the dextral megashear zone.
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The earthquake was caused by the sudden rupture and motion along a strike-slip fault, beneath Lincolnshire. Earthquake motion occurred over a time span of ~2 minutes but it was most intense and was felt at the surface for just 10 to 30 seconds; maximum vertical ground motion at the epicentre of the earthquake was only ~1 mm. The observed focal mechanism implies either sinistral motion on a N–S or dextral motion on an E–W oriented strike-slip fault. The nine aftershocks observed, ~ SSW of the main earthquake event, point to an approximately N–S oriented fault.
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European flounder, like other flatfish, experience an eye migration during their lifetime, making them asymmetrical. The most obvious characteristic of flatfish, other than their flatness, is their asymmetrical morphology: both eyes are on the same side of the head in the adult fish. In some families of flatfish, the eyes are always on the right side of the body (dextral or right- eyed flatfish), and in others, they are always on the left (sinistral or left- eyed flatfish). Primitive spiny turbots include equal numbers of right- and left-sided individuals, and are generally more symmetrical than other families.
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The island of Hispaniola lies across the complex transform plate boundary between the North American Plate and the Caribbean Plate. The overall four cm per year displacement along this boundary is split nearly equally between two major dextral (right lateral) strike-slip zones either side of the Gonâve Microplate. To the south is the Enriquillo–Plantain Garden fault zone, which extends from Jamaica in the west to the south-east of Hispaniola to the east. In the north the fault zone is the Septentrional- Oriente fault zone passing along the southern margin of Cuba and along the northern part of Hispaniola.
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The proposed four million years old tectonic aneurysm system in the Saint Elias Mountains in Alaska was formed by glacial erosion on the mountains developed by underthrusting of the Yakutat microplate beneath the North American margin. The aneurysm occurs in the Northern plate corner in which transitions from dextral strike-slip motion to thrust sense motion thereby focusing strain. The interpreted relationship between erosion mountain development has more variations between researchers than Himalayan systems due to the age of the system and constraints regarding field work due to glacier cover. In the St. Elias range collision and underthrusting caused surface uplift forming mountains.
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Much of the record of this deformation has been overridden by Tertiary age structures and the zone of Cretaceous dextral thrust faulting appears to have been widespread. It was also during this period when massive amounts of molten granite intruded highly deformed ocean rocks and assorted fragments from pre-existing island arcs, largely remnants of the Bridge River Ocean. This molten granite burned the old oceanic sediments into a glittering medium-grade metamorphic rock called schist. The older intrusions of the Coast Range Arc were then deformed under the heat and pressure of later intrusions, turning them into layered metamorphic rock known as gneiss.
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Southern Armenia lies within the complex zone of continental collision between the Arabian Plate and the Eurasian Plate, which extends from the Bitlis-Zagros belt in the south to the Greater Caucasus mountains, the Apsheron-Balkan Sill and the Kopet Dag mountains in the north. In Armenia the collision is strongly oblique with a large dextral (right lateral) strike-slip component. The Sardarapat- Nakhicheven fault system is formed of four left-stepping fault segments, the Kagyzman, Sardarapat, Parackar-Dvin and Nakhichevan faults. Movement on the Parackar-Dvin segment of this fault system has been associated with a series of large earthquakes in the second half of the 9th century.
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Much of the record of this deformation has been overridden by Tertiary age structures and the zone of Cretaceous dextral thrust faulting appears to have been widespread. It was also during this period when massive amounts of molten granite intruded highly deformed ocean rocks and assorted fragments from pre-existing island arcs, largely remnants of the Bridge River Ocean. This molten granite burned the old oceanic sediments into a glittering medium-grade metamorphic rock called schist. The older intrusions of the Coast Range Arc were then deformed under the heat and pressure of later intrusions, turning them into layered metamorphic rock known as gneiss.
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USGS ShakeMap for the event The earthquake occurred in an area of complex tectonics caused by the continuing collision between the northward moving Indo- Australian Plate and the Eurasian Plate, which created the Arakan Yoma mountains. In this zone of highly oblique collision, most of the motion is accommodated by the north-south trending Sagaing fault, a major dextral (right lateral) strike-slip fault that runs through the western and central part of Burma. The remaining component of shortening across this zone causes distributed deformation of eastern Burma and Thailand extending into Laos. This deformation is partly accommodated by a set of southwest-northeast trending sinistral (left lateral) strike-slip faults.
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Molise and Apulia lie above a series of thrust sheets that were emplaced northeastwards on top of the foreland of the Adriatic Plate due to continental collision during the Neogene. In the southern part of the Apennines, the thrusting is no longer active, but it continues in northern Italy along the southern margin of the Po Plain. The foreland to the east is characterised by zones of active west–east trending dextral (right-lateral) strike-slip faulting. The best described of these zones is the Mattinata Fault, which has a clear topographic expression on the south side of the Gargano Peninsula and has been traced offshore into the Adriatic Sea.
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The earthquake lasted between 25 and 30 seconds and had an estimated magnitude of 6.75 on the surface wave magnitude scale. The calculated focal mechanism is consistent with slightly oblique dextral (right lateral) strike-slip on a NW-SE trending fault plane, matching the orientation of other fault planes measured in the area and a marked bathymetric lineament. The fault parameters calculated for the earthquake are a length of 30 km, a width of 27 km and a slip of one metre. The NW trending nodal plane of this earthquake coincides with the strike of the NW trending Naqara Fault on the southeast coast of Viti Levu.
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Northwestern Iran and easternmost Turkey lie within the zone of complex structure associated with the continuing collision between the Arabian Plate and the Eurasian Plate. On this part of the boundary the collision is quite oblique and the thrust faulting along the front of the Zagros fold and thrust belt is accompanied by a series of NW–SE trending dextral (right-lateral) strike-slip faults, such as the North Tabriz Fault and the Gailatu–Siah Chesh-meh–Khoy Fault. Normal faults are developed at terminations and releasing bends on the strike-slip faults. The entire fault system is active and has been associated with many destructive earthquakes.
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Dextral (right lateral) strike slip motion is also observed along the fault scarp, this motion is reasonably expected due to the nearby right lateral Sagaing fault. Southward, the Shan Scarp ends at the junction with the Three Pagodas fault. Along the foothills of the Shan Scarp, steady-state stretching ductile deformation trending in NNW-SSE direction was identified and is compatible with the extensive force that generates the en-echelon pull apart basin in Myanmar Central Belt (MCB). The above evidence suggests ductile deformation along Myanmar Central Belt (MCB) should occur prior to the brittle deformation along Sagaing fault and the Shan Scarp fault.
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The La Tour-Blanche Anticline forms part of a system of anticlinal ridges in the northeastern Aquitaine Basin. During the time interval Uppermost Cretaceous till Eocene compressional movements coupled with considerable shearing motions were responsible in their genesis. Important to note is the rather regular spatial organisation of these structures, which extend ESE-WNW or SE-NW and follow in a dekakilometric spacing (15–20 km) the outline of the Massif Central. The southern Armorican Massif shows a rather similar spatial organisation in the eastern Vendée; here dextral shear zones in dekakilometric spacing and the intervening far less deformed synclinoria follow the same trend.
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The epicenter of the earthquake lies within a diffuse zone of seismicity known as the Azores–Gibraltar seismic belt, which marks the boundary between the African Plate and the Eurasian Plate. The deformation at this plate boundary is transpressional in style, with dextral (right lateral) strike-slip accompanied by slow convergence (4 mm/yr). Linear bathymetric features within this zone, such as the SW–NE trending Gorringe Bank, are thought to be a result of reverse faulting. Investigations using multibeam swathe bathymetry have revealed additional SW–NE trending reverse faults and fold axes and a set of WNW–ESE trending lineaments, interpreted as strike-slip faults.
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Flatfish are asymmetrical, with both eyes lying on the same side of the head European flounder, like other flatish, experience an eye migration during their lifetime. The most obvious characteristic of the flatfish is its asymmetry, with both eyes lying on the same side of the head in the adult fish. In some families, the eyes are usually on the right side of the body (dextral or right-eyed flatfish), and in others, they are usually on the left (sinistral or left-eyed flatfish). The primitive spiny turbots include equal numbers of right- and left-sided individuals, and are generally less asymmetrical than the other families.
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The TVF is located near the intersection of several faults and thrusts. It rests on what is known as the Tengchong block which is simply a region that is an extension of the southern Tibetan Plateau. The Tengchong block is bounded by the Sagaing Shear Zone and the Tsangpo Suture located to the West, and the north–south trending strike-slip Jinsha-Red River Fault and the dextral strike-slip Gaoligong shear zone located to the East and the Ruili fault to the southeast. Within the TVF, the India-Asian continent collision created a fault system that consists of predominantly north–south trending strike-slip faults.
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Scotland, geographical areas. The Southern Uplands Fault (or occasionally Southern Upland Fault)British Geological Survey, Bedrock Geology UK North, 1:625K map 5th edn 2007 is a fault in Scotland that runs from Girvan (or more specifically from the Rhins of Galloway) to Dunbar on the East coast. It marks the southern boundary of the Scottish Midland Valley and the northern margin of the Southern Uplands; indeed it is recognised as a boundary between these two terranes. Both sinistral and dextral strike-slip movement is recorded from parts of the fault as are down-north and down-south normal movements suggestive of a complex history.
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The protoconch consists of 2½ whorls, dextral, strongly rounded and smooth, The subsequent whorls show a strong shoulder one-third of the distance between the sutures anterior to the summit, the rest well rounded. They are marked by strong, narrow, sinuous, slightly protractive, axial ribs, of which 10 occur upon the first, 12 upon the second and third, 14 upon the fourth and fifth, and 16 upon the penultimate whorl. The intercostal spaces are about three times as wide as the ribs. The spiral sculpture consists of moderately broad, low, flattened spiral lirations, separated by channels a little less in width than the lirations.
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Although this notch is not as well developed as elsewhere in the family, the shell feature is nonetheless visible in an adult dextral (normal right- handed) specimen, as a secondary anterior indentation in the lip, to the right of the siphonal canal (viewed ventrally). The animal's left eyestalk protrudes through this notch. The spire is a protruding part of the shell that includes all of the whorls except the largest and final whorl (known as the body whorl). It is usually more elongated than in other strombid snails, such as the closely related and larger goliath conch, Lobatus goliath that is endemic to Brazil.
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Solea aegyptiaca is a dextral flatfish with on oval body shape which is brownish grey on the eyed side, with the eyed side pectoral fin being largely coloured black. The left, uneyed, side is white. It is very similar to the common sole, with which it is sympatric, but the vertebrate count and fin ray count differ. S. aegyptiaca has 39-44 vertebrae to the common sole's 46-52, while the dorsal fin of S. aegyptiaca has 62-87 finrays to the common sole's 69-97 finrays, other finray counts are pectoral fin on eyed side with 7-9 to 9-10, anal finrays 51-72 compared to 53-79.
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The 10 kilometer wide Ross Lake fault zone (RLFZ) is part of a 500 kilometer long zone of high-angle faults in the North American Cordillera of Washington and Canada. The RLFZ consists of two major sets of faults. The eastern set of the Hozameen and Slate Creek faults and more southerly North Creek fault form the western boundary of the Jurassic-Cretaceous Methow River basin and in part separate it from metamorphic equivalents of Methow strata. Minor structures along the North Creek fault record dextral strike-slip events that occurred between approximately 88 and 50 Ma. The same formations lie on both sides of the faults, implying modest slip (10s of km?).
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The Ibagué Fault forms part with the Garrapatas and Cucuana Faults a shear zone between the latitudes 4 and 5 degrees north. To the north of this zone, regional structures are oriented along a north-northeast strike, characterised by sinistral displacement, among others the San Jerónimo, Silvia-Pijao, Cauca-Almaguer, Murindó, Bituima-La Salina and Bucaramanga-Santa Marta Faults. The movement along these structures generates a transpressive tectonic regime, related to the collision of the Chocó Block in the west of Colombia, during the Late Miocene. To the south of the structural zone the Ibagué Fault belongs to, north-northeast striking faults are mostly dextral, such as the Buesaco- Aranda, Cali-Patía and Algeciras Faults.
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Most people agree that the South-Eastern portion of the fault merges into and parallels the Indus Suture Zone in South West Tibet. The southern segment of the Karakoram Fault shows that only 120 km of dextral motion is evident from offset of geologic features, such as the Indus River and the South Kailas Thrust, and that the strain in this region is almost entirely accommodated for by a north-south shortening in the Himalaya, just south of the Indus Suture Zone. The Neogene Gar Basin in western Tibet also accommodates slip along the Karakoram fault. The basin lies within the northern approximately 1 km wide area of the fault, and contains listric normal faults.
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The Bogotá Fault () is a major inactive slightly dextral oblique thrust fault in the department of Cundinamarca in central Colombia. The fault has a total length of , while other authors designate a length of , and runs along an average north-northeast to south-southwest strike of 013.5 ± 7 across the Altiplano Cundiboyacense, central part of the Eastern Ranges of the Colombian Andes. The fault stretches from the Gallo River at the Sumapaz Páramo in the south to the Teusacá River in the north and borders the Bogotá savanna and the Colombian capital to the east. The Bogotá Fault formed the pronounced Eastern Hills, with the well-known Monserrate and Guadalupe Hills, east of the Colombian capital.
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Ranchería River in Distracción Ranchería River in Fonseca The Cesar-Ranchería Basin is located to the southeast of the Sierra Nevada de Santa Marta The Cesar-Ranchería Basin is an intermontane foreland basin enclosed by two main mountain ranges; the northernmost Andean Serranía del Perijá in the southeast of the basin and the triangular Sierra Nevada de Santa Marta to the northwest. The northeastern limit is sharply formed by the dextral strike-slip Oca Fault, while the Bucaramanga-Santa Marta Fault forms the boundary to the west. The faults form the border with the Guajira Basin and Middle Magdalena Valley respectively. The basin has a general orientation of 30 degrees from north.
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Dextral slickenside of pyrite The mechanisms of shearing depend on the pressure and temperature of the rock and on the rate of shear which the rock is subjected to. The response of the rock to these conditions determines how it accommodates the deformation. Shear zones which occur in more brittle rheological conditions (cooler, less confining pressure) or at high rates of strain, tend to fail by brittle failure; breaking of minerals, which are ground up into a breccia with a milled texture. Shear zones which occur under brittle-ductile conditions can accommodate much deformation by enacting a series of mechanisms which rely less on fracture of the rock and occur within the minerals and the mineral lattices themselves.
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The opening of the South Atlantic Ocean divided West Gondwana (South America and Africa), but there is a considerable debate over the exact timing of this break-up. Rifting propagated from south to north along Triassic–Early Jurassic lineaments, but intra-continental rifts also began to develop within both continents in Jurassic–Cretaceous sedimentary basins; subdividing each continent into three sub-plates. Rifting began at Falkland latitudes, forcing Patagonia to move relative to the still static remainder of South America and Africa, and this westward movement lasted until the Early Cretaceous . From there rifting propagated northward during the Late Jurassic or Early Cretaceous most likely forcing dextral movements between sub-plates on either side.
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The Osbourn Trough, located at 25.5°S just north of the Louisville Ridge collision zone, is a -long extinct spreading ridge located midway between two large oceanic plateaux north and south of the Tonga Trench respectively: Manihiki to the north and Hikurangi to the south. These plateaux once formed part of the Ontong Java-Manihiki- Hikurangi large igneous province (LIP). Spreading between the plateaux ceased when Hikurangi collided with the Chatham Rise east of New Zealand at 86 Ma. The western end of the Osbourn Trough is bounded by the Tonga Trench and its eastern by the Wishbone–East Manihiki Scarp. In between the Osbourn Trough is divided into three segments separated by dextral offsets.
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Satellite radar image showing ground motion effects during the 2016 Kaikoura earthquake Map of the Marlborough Fault System The Kekerengu Fault is an active dextral (right lateral) strike-slip fault in the northeastern part of South Island, New Zealand. It is closely associated with the Hope Fault and Jordan Thrust at its south-easternmost edge and likely joins with the Clarence Fault to form the Wairarapa Fault offshore in Cook Strait. Early investigations immediately following the 14 November 2016 Kaikōura earthquake indicate that up to of motion may have occurred on the Kekerengu Fault during the 7.8 magnitude quake. During this earthquake the offshore continuation of the Kekerengu Fault to the north east, known as the Needles Fault, ruptured as well.
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The Mendocino Fault is seismically active with mostly small and moderate earthquakes, but the largest event that was unequivocally associated with the fault was the M6.9 earthquake on September 1, 1994, at 125.8 W longitude. Aftershocks of that event with corresponding dextral strike-slip focal mechanisms occurred farther to the east and close to the Mendocino Triple Junction. Another large event (7.3–7.6) occurred on January 31, 1922 (with an aftershock of M7+ the next day) but the sources of these shocks could not be determined with any precision as the first seismographs did not arrive in the area until 1932. Due to their offshore epicenters all of these events caused little damage though were felt across a broad area.
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However, the amount of shortening that has taken place on the thrust is not connected to Eocene extension due to the Rocky Mountain trench fault system and the Flathead fault having no influence positionally on the footwall and hanging wall cutoffs of the Lewis thrust. Instead, this transpression was replaced with transtension in the early Eocene involving east-west crustal extension and tectonic exhumation, which brought up mid-crustal metamorphic rocks to the surface to be exposed. Additionally, this transition from transpression to transtension resulted in rapid cooling of the metamorphic core complexes as they were exhumed and brought to the surface. Dextral transtension on intracontinental strike-slip faults in northeastern and southwestern British Columbia culminated with the mid Eocene extensional exhumation of midcrustal metamorphic core complexes.
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Like most other gastropods, the shell of this species is almost always right-handed, or dextral, in its shell-coiling, but very rarely a left-handed shell is found (one in approximately 200,000 individuals). In the Hindu religious context, the very rare left-handed (sinistral) shells of this species are known as Dakshinavarti Shankh in Sanskrit or Valampurich chanku in Tamil, as opposed to the more common right-handed forms, which are known as Vamavarti. The Dakshinavarti is particularly highly valued in terms of its religious significance. In its religious context, the Dakshinavarti shankh is considered to be right-handed, because the "handedness" of the shell coiling is measured with the "spout" or siphonal canal of the shell pointing upwards.
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Pacific Ocean depth map showing the Heezen Fault and the Tharp Fault as #17. The Eltanin Fault System (Eltanin Fracture Zone) is a series of six or seven dextral transform faults that offset the Pacific-Antarctic Ridge, a spreading zone between the Pacific Plate and the Antarctic Plate. The affected zone of the Pacific-Antarctic Ridge is about 800 km long, between 56° S, 145° W and 54.5° S, 118.5° W, southwest of Easter Island, and about as far as one can get from land on planet Earth (48°52.6′S 123°23.6′W).Because of the generally remote character of the epicentral area (the Eltanin FZ is indeed close to the point at sea farthest away from any land shore) page 10.497, However, the total offset is about 1600 km.
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Shells of two different species of sea snail: on the left is the normally sinistral (left-handed) shell of Neptunea angulata, on the right is the normally dextral (right-handed) shell of Neptunea despecta The shell of a large land snail (probably Helix pomatia) with parts broken off to show the interior structure. 1 – umbilicus 2 – columellar plait 3 – aperture 4 – columella 5 – suture 6 – body whorl 7 – apex Four views of a shell of Arianta arbustorum: Apertural view (top left), lateral view (top right), apical view (bottom left), and umbilical view (bottom right). The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage.
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Because of its depth and the computed focal mechanism, the first earthquake is thought to have resulted from deformation within the mantle of the descending Australian plate, rather than from movement on the plate boundary itself. A second event, which measured 6.6 , struck the province of Jambi in central Sumatra, 01:52:29 local time on 1 October 2009 at a depth of , about 46 kilometres south-east of Sungaipenuh. Although it was in the same region, the United States Geological Survey specified that it was not an aftershock, as it was located too far from the initial quake. The second earthquake has been linked to dextral (right-lateral) movement on the Great Sumatran fault, which takes up the strike-slip component of the convergence between the two plates.
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The western and central parts of Turkey lie on the eastern part of the Anatolian Plate, which is currently being forced to the west by the continuing northward movement of the Arabian Plate. In northern Turkey, this westward motion is taken up by a major zone of dextral (right-lateral) strike-slip, the North Anatolian Fault. The 1999 Düzce event is the most recent in a sequence of large earthquakes that have affected the North Anatolian Fault, starting towards the eastern end with the 1939 Erzincan earthquake, then propagating towards the west with events in 1942, 1943, 1944, 1951, 1957, 1967 and finally the 1999 İzmit event. At its western end the North Anatolian Fault splits into two main segments, with the northern of these giving rise to the 1999 earthquakes.
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In some families the eyes are always on the right side of the body (dextral or right-eyed flatfish) and in others they are always on the left (sinistral or left-eyed flatfish). The primitive spiny turbots include equal numbers of right- and left-eyed individuals, and are generally less asymmetrical than the other families. Other distinguishing features of the order are the presence of protrusible eyes, another adaptation to living on the seabed (benthos), and the extension of the dorsal fin onto the head. Amphistium is a 50-million-year-old fossil fish identified as an early relative of the flatfish, and as a transitional fossil In Amphistium, the transition from the typical symmetric head of a vertebrate is incomplete, with one eye placed near the top-center of the head.
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Topographic map showing the Red River and fault The Red River (Nansha Reservoir) seen from the slope of its deep valley, south of Potou Township, Jianshui County The Red River Fault or Song Hong Fault () is a major fault in Yunnan, China and Vietnam which accommodates continental China's (Yangtze Plate) southward movement It is coupled with that of the Sagaing Fault in Burma, which accommodates the Indian plate's northward movement, with the land (Indochina) in between faulted and twisted clockwise. It was responsible for the 1970 Tonghai earthquake. It is named after the Red River which runs through the valley eroded along the fault trace. The Red River Fault was a sinistral strike-slip shear zone until Miocene times when it became reactivated as a brittle dextral strike-slip fault.
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The Salton Trough is part of the complex plate boundary between the Pacific Plate and the North American Plate where it undergoes a transition from the continental transform of the San Andreas Fault system to the series of short spreading centers of the East Pacific Rise linked by oceanic transforms in the Gulf of California. The southern part of the trough is divided into two by the Sierra Cucapa and Sierra Mayor ranges forming the Mexicali Valley to the east and the Laguna Salada to the west. The western side of these ranges is formed by the Laguna Salada Fault, which forms a possible continuation of the Elsinore Fault Zone of southern California. The Laguna Salada Fault shows combined normal (down to the southwest) and dextral (right-lateral) movement.
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Testis subspherical, lying immediately posterior to germarium; proximal vas deferens not observed; seminal vesicle a simple dilation of distal vas deferens, lying just posterior to MCO; ejaculatory bulb apparently absent; large vesicle (prostatic reservoir?) with translucent contents lying dorsal to common genital pore. MCO reniform, quadriloculate, with moderately long cylindrical distal cone; distal tube with delicate wall; terminal filament delicate, variable in length; walls of three distal chambers comparatively thick; proximal chamber with delicate wall, frequently collapsing during mounting of specimen on slide. Germarium pyriform; germarial bulb lying slightly to right of body midline, with elongate dorsoventral distal loop around right intestinal cecum; ootype lying slightly to left of body midline, with well-developed Mehlis’ gland and giving rise to delicate banana-shaped uterus when empty. Common genital pore ventral, dextral to distal chamber of MCO.
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In the third week of fetal development the rudimentary heart (bilaterally symmetrical cardiac tube) undergoes a characteristic dextral looping, forming an asymmetrical structure with bulges that represent the incipient ventricular and atrial chambers of the heart. Arising from cells derived from the primary heart field in the cardiac crescent, HAND1 goes from being expressed on both sides of the heart tube to the ventral surface of the caudal heart segment and the aortic sac, then being restricted to the outer curvature of the left ventricle in the looped heart. In conjunction with HAND2 (a fellow bHLH transcription factor), complementary and overlapping expression patterns are thought to play a role in interpreting asymmetrical signals in the developing heart which leads to the characteristic looping. The two are implemented in cardiac development of embryos based on a crucial HAND gene dosage system.
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Relief Map of Metro Manila and nearby provinces showing the surface traces of the West and East Valley Faults The fault contains two major segments, known as West Valley Fault (WVF) and East Valley Fault (EVF). ;West Valley Fault Lower and upper fault plain along the West Valley Fault in Canlubang Golf, Country Club The west segment, known as the West Valley Fault (WVF) is one of the two major fault segments of the Valley Fault System which runs through Metro Manila to the cities of Marikina, Quezon City, Pasig, Makati, Taguig and Muntinlupa and moves in a dominantly dextral strike-slip motion. The West Valley Fault segment traverses from Doña Remedios Trinidad to Calamba with a length of . The West Fault is capable of producing large scale earthquakes on its active phases with a magnitude of 7 or higher.
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The Kern Canyon Fault (Late-Quaternary Active Kern Canyon Fault) is a dextral strike-slip fault (horizontal) that runs roughly around 150 km (93 mi) beside the Kern Canyon River through the mountainous area of the Southern Sierra Nevada Batholith. The fault was a reverse fault in the Early Cretaceous epoch during the primal stages of the Farallon Plate subduction beneath the North American Continental Plate and fully transitioned into a strike-slip shear zone during the Late Cretaceous. Professor Robert W. Webb of the University of Chicago was the first to research the fault in 1936; He found a lava flow (Pliocene age) that covered the northern end of the fault trace where the Little Kern and Kern River coincided. Without any evidence of deformation affecting the hardened lava and without any evidence found previously when investigating the fault line, Webb deemed the fault to be inactive.
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The eastern part of Bangladesh and the southwestern part of Burma lie along the highly oblique convergent boundary between the Indian Plate and the Eurasian Plate. The degree to which this deformation is partitioned into zones of thrust tectonics (accommodating that part of the motion perpendicular to the boundary) and strike-slip tectonics (accommodating the northward movement of the Indian Plate) varies along the boundary. A pure strike-slip boundary that strike parallel to the plate vector runs along the Western Burma Scarp, that is replaced to the north by the Indo-Burmese Wedge fold and thrust belt, at the western edge of the boundary zone, and a series of major dextral (right lateral) strike-slip faults, particularly the Kabaw Fault and Sagaing Fault further to the east. The presence of active subduction along the eastern margin of the Bay of Bengal is disputed.
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Metamorphic zones, and Moine Thrust Belt, Great Glen Fault and Highland Boundary Fault Euramerica in the Devonian (416 to 359 Ma) with Baltica, Avalonia (Cabot Fault, Newfoundland and Great Glen Fault, Scotland) and Laurentia The Great Glen Fault has a long movement history. It formed towards the end of the Caledonian orogeny associated with the collision between the Laurentia and Baltic tectonic plates at the end of the Silurian continuing into the Early Devonian (likely age range 430–390 Ma (million years)). The movement at that time was sinistral (left-lateral), the same as the closely related set of faults sub-parallel to the main part of the Great Glen Fault, which include the Strathconon Fault and Strathglass Faults to the northwest and the Laggan Fault, Tyndrum Fault, and Ericht-Laidon Fault to the southeast. The second main phase of movement was during the Carboniferous, this time with a dextral sense.
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The Transverse Ranges result from a complex of tectonic forces and faulting stemming from the interaction of the Pacific Plate and the North American Plate along the dextral (right slip) San Andreas Fault system. Their orientation along an east–west axis as opposed to the general northwest–southeast trend of most California ranges results from a pronounced left step in the San Andreas Fault that occurred in Pliocene time ( million years ago) when southern reaches of the fault moved east to open the Gulf of California. The crust within the Pacific Plate south of the ranges can not easily make the left turn westward as the entire plate moves northwestward, forcing pieces of the crust to compress and lift. Prior to this shift of the fault to create the left bend, northwest–southeast trending rock belts in all of the Transverse Ranges began to rotate clockwise in the right shear of Pacific Plate – North American Plate motion.
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320px The Sandwick Fish Bed near 260px Thick fluvial sandstones of Givetian age exposed in the cliffs on the western coast of 260px 260px In common with the Devonian basins of Norway and East Greenland, the Orcadian Basin lies entirely within the area affected by crustal thickening during the Caledonian orogeny. The recognition of extensional faulting at various scales in these areas at the same time as deposition led to the suggestion that these basins reflect the gravitational collapse of this thickened zone. Other tectonic models have suggested that transtensional sinistral (left lateral) strike-slip movement on the Great Glen Fault, which passes through the centre of the basin, was the main cause of basin formation. The continuity of Middle Devonian facies belts across the trace of the fault zone, after accounting for subsequent reactivation of the Great Glen Fault in a dextral sense, has been used to argue against strike-slip activity during sedimentation.
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This can be done on a large scale (over many kilometersRichard Oliver Lease, Nadine McQuarrie, Michael Oskin, and Andrew Leier, 2009, Quantifying Dextral Shear on the Bristol-Granite Mountains Fault Zone: Successful Geologic Prediction from Kinematic Compatibility of the Eastern California Shear Zone, Journal of Geology, volume 117, p. 37–53), a small scale (inside a single outcrop or fault trenchS Baker, 2005, Pseudotachylyte-generating faults in Central Otago, New Zealand, Tectonophysics, Volume: 397, Issue: 3-4, Publisher: Elsevier, Pages: 211-223) or even a single hand sample/rock (see image). Items that are usually used in a piercing point study include large geologic formations or other rock units that can be matched either stratigraphically, geochemically, or by age dating. Features that are linear or planar, like a stratigraphic unit, are much better for use in a piercing point study than a rounds or irregular-shaped objects, such as a pluton, because the reconstruction is always more precise with a more predictable shape (because of the Principle of lateral continuity).
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Lake Tahoe is the youngest of several extensional basins of the Walker Lane deformation zone that accommodates nearly per year of dextral shear between the Sierra Nevada-Great Valley Block and North America. Three principal faults form the Lake Tahoe basin: the West Tahoe Fault, aligned between Meyers and Tahoe City, and which is the local segment of the Sierra Nevada Fault, extending on shore north and south of these localities; the Stateline/North Tahoe Fault, starting in the middle of the lake and creating the relief that forms Stateline, NV; and the Incline Village Fault, which runs parallel to the Stateline/North Tahoe Fault offshore and into Incline Village. The West Tahoe Fault appears to be the most active and potentially hazardous fault in the basin. A study in Fallen Leaf Lake, just south of Lake Tahoe, used seafloor mapping techniques to image evidence for paleoearthquakes on the West Tahoe and revealed the last earthquake occurred between 4,100 and 4,500 years ago. Subsequent studies revealed submarine landslides in Fallen Leaf Lake and Lake Tahoe that are thought to have been triggered by earthquakes on the West Tahoe fault and the timing of these events suggests a recurrence interval of 3,000–4,000 years.
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