A lineament, he explained, is a possible indication that there is a fracture in the earth's surface deep below the ground.
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But mapping of gravitational anomalies shows a definite lineament, some 700 km (about 400 miles) long, called the Klamath- Blue Mountain Lineament (KBML).. This lineament is of interest here because of the possibility it was formerly conjugate with OWL, discussed in the next section.
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It forms a volcanic chain with Llullaillaco that extends towards Antofalla and Galán. This lineament is known as "Archibarca lineament". Cerro Corrida de Cori and Cerro Negro are associated with the intersections between this lineament and ENE lineaments. Fault zones on the area have controlled the magma ascent, probably facilitating the eruption of fairly primitive basaltic lavas.
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Rock type is predominantly andesite. Tectonically, Panay lies at the intersection of two major regional trends, the Bataan Lineament and the Palawan-Macolod Lineament. Batangas Bay, which includes Panay, may be a drowned caldera.
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Lastarria and Cordón del Azufre, together with some more local volcanic centres, may be part of a larger silicic volcanic complex that has not yet formed a caldera. This complex is characterized by a high doming with a central depression. A major crustal lineament known as the Archibarca lineament intersects the main volcanic arc at Lastarria. Other volcanic centres such as Galán and ore deposits are also found on this lineament.
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The Jemez Lineament consists of the San Carlos volcanic field, Springerville volcanic field, Red Hill volcanic field, Zuni-Bandera volcanic field, Mount Taylor volcanic field, Jemez volcanic field and possibly the Ocate volcanic field, Raton-Clayton volcanic field, and Mesa de Maya. These are all young (Cenozoic) volcanic fields, showing some progression in age from southeast to northwest (across the Lineament) but no systematic progression in age along the Lineament. The Lineament is interpreted as a hydrous subduction zone scar marking the southern boundary of the pre-1.70 GYa Yavapai basement. Seismic imaging shows both north- and south-dipping reflections that converge at the core-mantle boundary.
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The village and its extensive parish sits astride the Malvern Line, a north-south aligned lineament originating in Precambrian times. To the east are Triassic sandstones whilst to the west are Devonian mudstones. Along the lineament itself are a complex mix of rocks of Precambrian, Cambrian and Silurian age.
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This change in composition geographically coincided with the volcanic activity crossing a lineament known as the Trotus line.
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There is also a Pb-isotopic boundary coincident with the Lineament. It is a zone of persistent crustal weakness.
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All of them appear to be associated with a lineament known as the Archibarca lineament, which crosses the Andes in northwest-southeast direction, and which additionally includes the Escondida ore occurrence and the volcanoes Llullaillaco, Corrida de Cori and Galán. This lineament may be an area where the crust is unusually weak. Other such lineaments in the Andes are the Calama-Olacapato-El Toro lineament and the Culampajá one. The terrain beneath the volcano is formed in part by the crystalline basement of Precambrian- Paleozoic ("Antofalla Metamorphites") age mainly north of the volcano and often interpreted as ophiolite, and by sedimentary units of Eocene-Miocene age that crop out on its southern side and by a conglomerate unit known as the Potrero Grande Formation.
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The Steep Belt forms a part of a much longer feature which extends from Pembrokeshire as far as Shropshire and Cheshire and is sometimes referred to as the Pontesford Lineament. The Lineament includes the Pontesford-Linley Fault, the Clun Forest Disturbance and the Red Rock Fault Zone which marks the eastern edge of the Cheshire basin.
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The Jemez Lineament is another, older feature, which also represents a linear weakness in the crust. The Lineament trends southwest to northeast, and underlies a string of volcanic features across Arizona and New Mexico. Those features include the San Carlos volcanic field, Springerville volcanic field, Zuni-Bandera volcanic field, Mount Taylor volcanic field and the Raton-Clayton volcanic field.
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Jump off Joe and the greater Horse Heaven Hills are anticlines within the Yakima Fold Belt. The belt is a series of fault lines extending throughout south-central Washington which are part of the larger Olympic-Wallowa Lineament. The lineament runs from Port Angeles to the Wallowa Mountains in northeastern Oregon.Field Trip Guide to the Columbia River Basalt Group Retrieved 31 May 2015.
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Another high conductivity body southeast of Tuzgle is associated with the Toro lineament and the Queva volcano and may also be hydrothermal in origin.
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Pocho volcanic field is a volcanic field in Argentina. It is associated with a crustal lineament known as the Ojo de Agua Lineament. It is located in the Sierras de Cordoba mountain chain. It formed during the late Miocene, when a progressive shallowing of the subducting Nazca Plate caused volcanic activity to retreat from the main Andes into the land behind the mountain chain.
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The Malvern Line or Malvern Lineament is the name applied to a north-south aligned lineament which runs through the Malvern Hills of western England and extends southwards towards Bristol and northwards past Stourport. It consists of a series of faults and folds which have the effect of bringing old Malvernian rocks to the surface. Being largely hard igneous rocks, the Malverns Complex rocks have resisted erosion better than those of the surrounding countryside and result in a striking line of hills of which the Malvern Hills are the most impressive. The Abberley Hills to their north also form a part of this lineament.
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Natib is part of the Western Bataan Lineament volcanic belt which includes the active Mount Pinatubo."Pinatubo Volcano" . Philippine Institute of Volcanology and Seismology. Retrieved on 2012-02-21.
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Location of the Olympic-Wallowa Lineament Is the OWL an optical illusion? The Olympic-Wallowa lineament (OWL) - first reported by cartographer Erwin Raisz in 1945. Now available on-line; see citation. on a relief map of the continental United States - is a physiographic feature of unknown origin in the state of Washington (northwestern U.S.) running approximately from the town of Port Angeles, on the Olympic Peninsula to the Wallowa Mountains of eastern Oregon.
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Guacha caldera is also closely linked to the neighbouring La Pacana caldera. The Guacha caldera forms a structure with the neighbouring Cerro Panizos, Coranzulí and Vilama calderas associated with a fault named the Lípez lineament. Activity along this lineament commenced with the Abra Granada volcanic complex 10 mya ago and dramatically increased more than a million years later. Volcanic activity is linked to this fault zone and to the thermal maturation of the underlying crust.
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A long crustal lineament known as the Anton Dohrn Lineament crosses through the seamount; it may extend into Scotland and Rockall Bank and runs in northwest–southeast direction. Anton Dohrn Seamount is probably formed mostly by basaltic lava and tuffs which define a transitional to alkaline suite. The rocks contain feldspar and olivine phenocrysts as well as plagioclase. They are covered with ferromanganese crusts and vesicles contain carbonates, clay and zeolites which formed through alteration.
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Several northeast trending discontinuities including the Mundrabilla lineament divide the Petermann orogeny, with extensive vertical offsets across them, usually west-side-up, though the timing of this event is unknown.
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Rock type is principally trachyandesite. K-Ar dating of about 1.14 million years was obtained from the Amorong volcanic group. It lies along the Eastern Bataan volcanic lineament of the Philippines.
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Elsewhere these layers are buried by Cenozoic rocks. There are several faults in the region, such as the Imilac-Salina del Fraile lineament whose movement has influenced the activity of Llullaillaco.
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The Pooranoo Metamorphics are intruded by granites of the Durlacher supersuite, which has been dated at 1680 Ma. The metamorphic grade of the Pooranoo Metamorphics varies, with two belts of different metamorphic character and timing during the Mangaroon orogeny recognised. These are divided by the Ti Tree Creek Lineament, a multiply reactivated fault which bisects the Gascoyne Complex. : North of the Ti Tree Creek Lineament the Pooranoo Metamorphics and Durlacher granites endured Abukuma Facies Series low-pressure, high-temperature Sillimanite grade metamorphism, with a date of 1680-1675 Ma returned from zircons : South of the Ti Tree Lineament, the Pooranoo Metamorphics and Durlacher granites endured a high-pressure, high-temperature Barrovian Facies Series metamorphic event, typically reaching garnet grade. This occurred at 1665 - 1650 Ma.
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The Central Wales Lineament is a north-south aligned zone of geological faults and folds which runs for scores of miles through Wales and which gives rise to a number of landscape features. The lineament lies along the axis of the Central Wales Syncline,Howells, M.F. 2007 British Regional Geology: Wales (Keyworth, Nottingham: British Geological Survey) p93 both following the generally northeast-southwest Caledonide trend though its central section is more north-south aligned.British Geological Survey 1996 Tectonic map of Britain, Ireland and adjacent areas. Pharoah, T.C. et al (compilers) 1:1,500,000 (Keyworth, Nottingham: British Geological Survey) The Tafolog Fault which runs north from Llanbrynmair is one component structure in the central section of the lineament and along which Cwm Tafolog has been eroded.
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Goodings, C.R. & Brookfield, M.E., 1992. Proterozoic transcurrent movements along the Kapuskasing lineament (Superior Province, Canada) and their relationship to surrounding structures. Earth-Science Reviews, 32: 147–185.Bleeker, W., and Pilkington, M., 2004.
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A "Montana--Florida Lineament" and even a "Mackenzie--Missouri Lineament" (from the Mackenzie River valley in the Yukon to Florida) have been claimed by Carey (see excerpts from his book), but are not generally recognized. For an interesting trip outside of mainstream science read about the Expanding Earth theory. There is a significant age discrepancy here. Whereas the OFZ is a mere 90 to 70 Ma old, this megashear is ancient, having been dated to the Mesoproterozoic - about a billion years ago.
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After merging into Patagonia, accretionary complexes developed west of it, meaning Chaitenia constituted a backstop. Chaitenia is not thought to extend beyond the Huincul lineament to the north, beyond which lies the Chilenia terrane.
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The southern segment of this lineament is where located the boundary of the Cascade orogen (the "Cenozoic Truncation Scar" in his Fig. 1). But this boundary is now known to be the South Whidbey Island Fault, which crosses Whidbey Island near Holmes Harbor and strikes southeast. The significance of this lineament and its offset is entirely unknown. That it seems to be expressed in Ice Age (16 Ka) deposits implies a very recent but entirely unknown event; but perhaps these recent deposits are only draped over a much older topography.
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Malumalu seamount lies in American Samoa and forms a topographic structure together with Savaii, Upolu and Tutuila close to the Tonga Trench which lies about south. Malumalu lies about south of Ofu island and is also known as "Southeast Bank". The seamount is a young volcano at the eastern end of a lineament that begins on Tutuila. This lineament has been named the "Malu trend" and contrasted to the "Vai Trend" farther northeast which runs between Ofu, Ta'u and Vailulu'u, comparable to the "Kea" and "Loa" trends in Hawaii.
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See also Line (geometry) A lineament is a linear feature in a landscape which is an expression of an underlying geological structure such as a fault. Typically a lineament will appear as a fault-aligned valley, a series of fault or fold-aligned hills, a straight coastline or indeed a combination of these features. Fracture zones, shear zones and igneous intrusions such as dykes can also be expressed as geomorphic lineaments. Lineaments are often apparent in geological or topographic maps and can appear obvious on aerial or satellite photographs.
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A meridional lineament of volcanoes including Limitayoc and Salle extends from the southern and western margin of the central lava domes to Cerro Pululu in the south. Another lineament may form the eastern rim of the lava dome complex. Other centres in the south are the Rose, Salle and West Zapaleri ignimbrites as well as the dacites of Cerro Bayo, all erupted 8.9–5.1 mya from the Vilama caldera. Cerro Panizos is associated with a large-scale topographic anomaly, similar to many other volcanic centres in the region.
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The Welsh Borderland Fault System is a zone of faulting and associated folding which runs northeastwards through Wales from Pembrokeshire through Carmarthenshire and Powys into Shropshire in England. It comprises the Tywi Lineament, Pontesford Lineament and Church Stretton Fault Zone.Brenchley, P.J. & Rawson, P.F. (eds) 2006 The Geology of England and Wales. The Geological Society, London (p80) The southern margin of the fault system is defined by the Church Stretton Fault and Dulas Valley Fault, amongst others whilst its northern margin is defined by the Garth-Llanwrtyd Fault Belt in Carmarthenshire.
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Some geologic evidence, including geochemistry and geographic indicators, imply that lithospheric detachment did occur beneath the southern Puna. Several major fault zones run across the Puna in the area, the most important being the Toro lineament to the south of Tuzgle. On this lineament, which has been subject to left-lateral displacement, are aligned several Pleistocene volcanoes, including Cordon Puntas Negras, Rincon, Tul Tul-Del Medio-Pocitos, Quevar, and Tastil (from north to south) (as well as the Negra Muerta volcanic complex). A segment named the Chorrillos fault is located directly south of Tuzgle.
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Location of the Aswa Dislocation The Aswa Dislocation, also called the Aswa mylonite belt, Aswa Lineament or Aswa Shear Zone is a north-west trending ductile shear zone that runs to the east of Lake Victoria in East Africa.
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The Taganga Fault is the tectonic lineament separating the village of Taganga from the Tayrona Park in the north.Sáenz Reyes, 2011, p.73 The activity of the NE-trending fault has produced carbonitization of the phyllites.Sáenz Reyes, 2011, p.
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The intersection between this lineament and the arc may act as a weakness zone that focuses the ascent of magma. Farther south lie volcanoes such as Wheelwright Caldera and Cerro Blanco, the last of which shows evidence of recent unrest.
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Many geological features in Western United States have a Northeastern orientation, the North American craton motion has the same orientation as well.Smith, R.L. and Luedke, R.G. (1984). For example: the Trans-Challis fault zone, Idaho; the Snake River in Oregon; the Garlock Fault, California; the Colorado River in Utah; the Colorado Mineral Belt; Crater Flat-Reveille Range-Lunar Crater lineament, the Northwestern Nevada volcanic field; the San Juan caldera cluster, Colorado; the Socorro-Magdalena caldera cluster, New Mexico; Jemez volcanic lineament (Raton hotspot trail); and the Yellowstone hotspot trail. But the Yellowstone hotspot trail was modified through faults and extension.
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Volcanic activity at Tata Sabaya and elsewhere in the Central Volcanic Zone is the consequence of the subduction of the Nazca Plate beneath the South America Plate. The volcano has developed along a lineament that separates older crust north of the lineament from younger crust in the south, and the edifice has been formed by andesitic rocks. The southern flank of Tata Sabaya failed during the latest Pleistocene about 12,000 - 12,360 years before present. Debris from the collapse entered a lake that covered the Salar de Coipasa at that time and formed a deposit with a volume of .
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Note that the ancient continental margin was not along the modern coast line (that runs due south from Vancouver Island), but turned in at the modern day Juan de Fuca Strait and followed the Olympic-Wallowa Lineament (OWL) towards southern Idaho,; . paralleling the general trend of faulting in British Columbia and the North Cascades. The Olympic-Wallowa Lineament (OWL) marks the approximate continental margin in the Late Cretaceous. The northeastward impact of part of Siletzia formed an embayment as indicated by the Darrington-Devils Mountain fault and the mélanges originally in front of the continental margin.
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The geological features at the dam site were evaluated for possibilities of displacement. The treatment measures implemented to address this condition involved excavation of a trench of width and depth below the toe slab which is meant to function as a concrete "socle". A grout curtain was also created through the "lineament" (fault line) and a grouting gallery was provided for the purpose that covered the downstream part of the embankment up to the toe-slab area near the lineament. Both the "socle" and the toe-slab incorporate movement joints consisting of compressible materials and a PVC water stop.
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El Negrillar volcano just north of Socompa; the white area to the right is part of the Socompa landslide deposit Socompa forms a northeast-trending alignment with neighbouring volcanoes such as Pular and Pajonales, which reach elevations of about . Monogenetic volcanoes were active in the area as well during the Pliocene and Quaternary and generated lava flows. One of these centres is El Negrillar just north of the collapse deposit, which was active during the Pleistocene and formed andesite-basaltic andesite lavas unlike the eruption products of Socompa itself. A long lineament known as the Socompa Lineament is associated with the volcano.
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A number of faults transect the region at La Pacana, including the north-south Miscanti Lineament and the Socompa and Quisiquiro lineaments. These lineaments or faults have influenced volcanism and geomorphology in the region, with volcanoes and vents aligning along these lineaments.
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Faulting relieved some stress and cleavage developed in the rocks. In the Fossey Mountains Trough, the intersecting folds have made dome and basin shaped structures. Uplift and erosion occurred. A quartz-feldspar porphyry intruded the Timbs Group in the southern Arthur Lineament at .
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Three major geologic lineaments occur in the region, the north-northwesterly trending Sajama lineament, a west-southwesterly one aligned with high topographical features and a west-northwesterly one. The west-southwesterly one played an important role in the development of Sajama volcano.
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It is found on the Wolf and Darwin Islands and the seamounts that connect them along the Wolf Darwin Lineament. It has a unique Pb ratio. WD is located along the northern side of the archipelago and dilutes to the east and south.
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Ash cones formed on the individual edifices. The lava flows on the table-shaped volcanoes also display rounded hollows. Many volcanoes appear to be part of a lineament. Volcanism may be influenced by strike-slip faults associated with the Jom-Bolok fault.
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As noted below, the deposited rocks of the Longmyndian show a variety of depositional facies that tell a story of ocean closure. The Longmyndian deposits rest upon Uriconian rocks but different sections are exposed exclusively between the Church Stretton Fault and the Pontesford-Linley Lineament.
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The volcano sits above a major local geological trend, the north–south Miscanti Line. Other volcanic centres are also located on this line, including the Corona and Saltar lava domes, and the Miscanti and Lejia volcanoes. The Miscanti Line dissects the Quaternary basement beneath Lascar, and it may be a hinge of a fold that is being propagated by faults. The formation of the first cone at Lascar may have been facilitated by the intersection between the Miscanti Line and another east–west lineament formed by Pliocene–Pleistocene tectonic compression of the region, and the lineament would have worked as an ascent path for magma.
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Eagle RockParticularly noticeable are the numerous plunging anticlinal noses at the northeastern end of the Smoke Holes.Sites, Roy S. (2005), “The Smoke Hole Region of West Virginia” at the West Virginia Geological and Economic Survey website. The Cave Mountain anticline consists of subparallel northeast-trending folds and southeast- dipping thrust faults with a maximum stratigraphic displacement of approximately 1900 feet, throwing Lower Silurian rocks against Lower Devonian rocks. The Cave Mountain anticline is further structurally bounded to the northeast and southwest by major cross-strike structural discontinuities: the nearly east-west trending Petersburg lineament and an extension of the northwest-southeast trending Parsons lineament, respectively.
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Siletzia, from Vancouver Island (Van) to the Klamath Mountains in Oregon. The shaded area shows near-surface extent as inferred from magnetic and gravitational studies (; ), divided into the Crescent (CR) and Siletz (SZ) terranes; the crossed dashed lines are alternate locations of CR-SZ boundary. Outcrops (with names) in black; ages (in red, Ma = millions of years) on the left are from , ages on right are from . The blue line is the Columbia River (Washington—Oregon boundary), the red line is the Corvallis—Waldo Hills fault, the dashed blue lines are the Olympic-Wallowa Lineament (OWL) and Klamath—Blue Mountains Lineament (KBML), and the red triangles are the main Cascades Volcanoes.
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Rock type is predominantly biotite, hornblende, and andesite, with dacite flows and dacitic tuffs similar to nearby Mount Natib. Mount Mariveles is on the Western Bataan Lineament volcanic belt of Luzon, which includes Mount Pinatubo, site of the second largest eruption of the last 20th century.
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These cones are part of the Peinado lineament and a sample was dated 200,000 years ago by argon chronology. They are noteworthy for their olivine phenocrysts. One lava flow less than one million years old reaches a length of . The western slopes contain dacitic lava domes.
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The volcano is part of the San Pedro-Linzor lineament, a long volcanic chain that extends northwest-southeastward. It was constructed on top the Toconce and Sifon Ignimbrites. The alignment was active during the late Pleistocene–Holocene and contains San Pedro-San Pablo–Paniri–Cerro del León–Toconce–Linzor.
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Precambrian provinces of western North America. The Jemez Lineament is coincident with the Yavapai-Mazatzal boundary. The Jemez Lineament is a chain of late Cenozoic volcanic fields, 600 km long, reaching from the Springerville and White Mountains volcanic fields in East-Central Arizona to the Raton- Clayton volcanic field in Northeastern New Mexico. It was long interpreted as a hot spot trace (Raton hot spot) due to its resemblance in length and azimuth to the Yellowstone hot spot trace, but there is no systematic progression in age along the trace and it is now interpreted as a hydrous subduction zone scar, separating basement rock of the Yavapai-Mazatzal transition zone from the Mazaztl Province proper.
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The west side of central Puget Sound, Holmes Harbor, and Saratoga Passage forms a lineament (between blue bars) that is offset at Port Madison (red bar). Another notable feature that crosses the OWL is Puget Sound, and it is curious to consider the possible implications of a Puget Sound Fault. (Such a fault was once proposed. on the basis of certain marine seismic data, but the proposal was stiffly rejected, and now seems to have been abandoned.) Combined terrestrial and bathymetric topography shows a distinct lineament along the west side of Puget Sound from Vashon Island (just north of Tacoma) north to the west side of Holmes Harbor and Saratoga Passage on Whidbey Island (see image).
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The western half of the Easter hotspot chain, a lineament that includes the Line Islands and Tuamotu archipelago, begins near the eastern part of the MPM. The formation of the MPM thus probably occurred at the Pacific-Farallon Ridge and the Easter hotspot, or where the Easter Microplate is now located.
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The Romeral Fault System is named after the volcano Romeral, located in the centre of the fault zone. The system has received various names as Romeral Lineament (), Romeral Fault, Romeral Fault Zone,Sierra et al., 2012 Romeral Shear Zone, and many individual segments of the system are known by local names.Paris et al.
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Coranzuli is a back-arc caldera in the Andes, related to the Altiplano-Puna volcanic complex. It formed along the Lipez geological lineament about 6.6 million years ago. Volcanic ash samples found in the Coastal Cordillera of Chile may come from this volcano. The Rachaite () stratovolcano is located close to the caldera.
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The central section of the fault zone – where it crosses the apparent location of the Olympic-Wallowa Lineament – shows marked variation in the location of the strands and of the underlying structure, but the nature and significance of this is not understood. The fault extends for approximately 70 km (43 miles), p.
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The lineament dates to the Precambrian era and thus is much older than the East African Rift System. It probably extends northwest to Darfur in Sudan, perhaps along the Abu Gabra Rift, and perhaps southeast to the Lindi fault zone on the Indian Ocean coast, passing through the Kilimanjaro and Elgon volcanic centers.
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The Dundas Element has a smooth background with prominent north–south ridges. The Rocky Cape Element is densely packed with linear textures parallel to the Arthur Lineament, with the Smithton Syncline showing as a Y shape. King Island also shows north–south texture. Basalt south of Wynyard also shows a wrinkly magnetic signature.
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The maars appear to form a lineament with Ch'iyar Qullu. However, in terms of isotope ratios and geochemistry the eruption products of the maars bear no resemblance to these at Chiyar Qullu. Potassium-argon dating has yielded an age of less than 128,000 years ago on a lava bomb on Ñiq'i Quta.
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Oregon Rotation: Rotation of Siletzia (green) about a northern pivot point. The Klamath Mountains (blue) rotated with Siletzia, having been formerly adjacent to the Blue Mountains (also blue, and also since rotated) near the Idaho Batholith (right edge). Red dashed line is the Olympic-Wallowa Lineament. Original image courtesy of William R. Dickinson.
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Darwin Island is the remains of an extinct volcano that reaches above sea level. It is situated northwest of the main Galápagos Island group on the Wolf-Darwin Lineament, which extends from the Galápagos Platform to the Galápagos Spreading Center, a mid-ocean ridge separating the Nazca and Cocos tectonic plates. The formation of Darwin Island is different from the formation of the main Galápagos Islands. There are currently two theories on the formation of the lineament: the first is that magma rising from the mantle plume forming the main Galápagos Islands has been channelled towards the Galápagos Spreading Center; alternatively there has been a separate rise in magma caused by stress in the ocean lithosphere by a transform fault.
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Gullet Quarry and unconformity The Malvern Hills are formed of some of the most ancient rocks in England, mostly igneous and metamorphic rocks from the late Precambrian, known as the Uriconian, which are around 680 million years old. The Malvern Line or Malvern Lineament is the name applied to a north–south aligned lineament which runs through the Malvern Hills and extends southwards towards Bristol and northwards past Kidderminster. It consists of a series of faults and folds which have the effect of bringing old Malvernian rocks to the surface. Being largely hard igneous rocks, they have resisted erosion better than those of the surrounding countryside and result in a striking line of hills of which the Malvern Hills are the most impressive.
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Volcanism of the Kostakan cones belongs to a pattern of basaltic volcanism that is recognized to the west of Kamchatka's Eastern Volcanic Zone (GVP). The Kostakan cones are found south of Bakening volcano, from Kostakan Lake southward in a north-south lineament (GVP). They are associated with lava flows and maars. (Ponomareva et al. 2007).
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See also www.MantlePlumes.org. In summary, the Brothers Fault Zone, and the related Eugene-Denio, McLoughlin, and Vale zones, appear to be deep-seated structures in accreted terranes bounded by the Klamath—Blue Mountains Lineament, which has been reactivated by Basin and Range extension, and exploited by mid-Miocene volcanism associated with the Yellowstone Hotspot.
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Gold and other minerals are precipitated from this fluid and have accumulated in the Sierra Nevadan metamorphic belt region in features called veins. The Smartville Block's eastern margin is the Rescue Lineament-Bear Mountains fault zone, and generally defines the range of gold- bearing veins of the Mother Lode region, important in the history of the California Gold Rush.
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The Bagre Norte Fault branches from the Palestina Fault, close to the Alicante River. The fault juxtaposes Precambrian metamorphic rocks on the east against sedimentary rocks in the west. The fault shows as a prominent topographic lineament on satellite images and aerial photographs. Prominent scarp faces west, the fault appears to displace erosion surfaces of the Central Ranges about .
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An integration of GIS and remote sensing in groundwater investigations: A case study in Burdur, Turkey. Hydrogeology Journal, 13, 826–834. Remote sensing collected data for geology and lineament density while GIS derived drainage density, topography elevation, gradient, landuse and the annual rainfall data. With weighted overlay, a groundwater potential map is generated to locate possible new water sources.
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The earthquake was preceded by foreshocks in the few days before the mainshock. The meizoseismal area extends 70 km in a SSW-NNE direction and is 30 km across. The earthquake may have been caused by movement on the SSW-NNE trending Fanjiaba-Linjiang Fault. This fault correlates well with a 30 km long lineament seen on satellite images.
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The Pleistocene snow line was located at altitude and moraines formed on the northern, western and southern flanks. Perhaps volcanically pre-formed cirques also developed. Cerro Chela is located south of Aucanquilcha, from which it is separated by the . It forms a lineament with Cerro Carcote, Cerro Palpana, Miño Volcano and Volcan Las Cuevas that is oriented north-south.
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Cerro del León is a stratovolcano located in El Loa province, Antofagasta Region, Chile. It is part of the Chilean Central Volcanic Zone and forms a volcanic lineament with neighbouring Paniri and Toconce that was active into the Holocene. Cerro del León itself was constructed in three stages by andesitic–dacitic lava flows and was subject to glacial erosion.
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Whitten & Brooks, The Penguin Dictionary of Geology 1972 The Trans Brazilian Lineament and the Trans-Saharan Belt, taken together, form perhaps the longest coherent shear zone on the Earth, extending for about 4,000 km. Lineaments have also been identified on other planets and their moons. Their origins may be radically different from those of terrestrial lineaments due to the differing tectonic processes involved.
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The lower flow ( wide and long) is thinner and contains pyroxene phenocrysts, the upper one has a smaller extent ( long) and is dominated by olivine. On its western margin, it borders a lineament that cuts through the cones. The eastern cone has no less than four lava flows dominated by olivine, one of which is long. Two other lava fields are also present.
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The Kunturiri volcanic complex 3-2.2 million years ago was the origin of the large Lauca-Perez Ignimbrite, which covered about of land with over and reached as far as the Pacific Ocean, leaving a distinctive landscape on the Altiplano. The eruption left a caldera now presumably buried underneath the Kunturiri volcanic complex. While the volcanic complex was once considered to be 7-9 million years old, later efforts have found younger ages and argon-argon dating has yielded ages of 650,000 ± 70,000 years ago for rocks erupted from the Kunturiri volcanic complex; there is no fumarolic activity at Kunturiri, but Kakepe has hydrothermal activity. Other volcanoes in the area are Pomerape and Parinacota which are constructed on the so-called Condoriri lineament together with Kunturiri; this lineament may act as a magma pathway to the three volcanoes.
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Remote sensing techniques provide evidence such as observed lineament, global scale mountain distribution, seismicity and volcanic activities to support crustal scale tectonics and geodynamics studies. Additional spectral information also helps. For example, the grain size differentiates snow and ice. Aside from a planar geological map with cross-sections, sometimes 3-dimensional view from stereo-photos or representation in Digital Elevation Model (DEM) could aid the visualization.
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Diabase and intruded rhyolites have also been identified in the sediments. All of the Salton Buttes, except for Mullet Island, have developed on a lineament, a linear feature with a conspicuous magnetic anomaly. The volcanoes seem to share a common feeder dyke. This dyke may be connected to deep-seated extensional processes along a transform fault that links the San Andreas Fault to the Gulf of California.
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The Burnie Formation followed in the Tonian period south east of the lineament with greywacke and slaty mudstone, and also some basic pillow lavas. The Oonah Formation has even more varieties of rock than the Burnie formation, also including conglomerate, quartz sandstone, dolomite and chert. The Bowry Formation in the Cryogenian was intruded by granite (Bowry granitoids) . These have been metamorphosed to the blueschist level.
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Its motion has been explained as the tip of a propagating crack produced by the twisting of the North Island's crust. Alexandra Volcanic Group rocks (mostly basalt) cover about 450 km2 amounting to 55 km3 from at least 40 vents. Mount Pirongia and Mount Karioi are part of a lineament in the group.Geology of the Raglan-Kawhia Area: Institute of Geological & Nuclear Sciences (N.
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The Thirty-Eight Parallel Lineament is one of Missouri's unique structural features, a 10- to 20-mile wide area of folds, faults and shattered bedrock from the Kansas state line to Vernon County to the Mississippi River in Ste. Genevieve County. It contains the widespread Ste. Genevieve Fault and pockets of Paleozoic rock—particularly eight locations with broken, but rearranged groupings of igneous and sedimentary rocks together.
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Blair et al., Plume Ridge Interaction Darwin Island is the most northerly of the two peaks on the Wolf Darwin Lineament that reach above the surface. The other, Wolf Island, is approximately away, although there are other sub-surface peaks. The volcano that forms the island is extinct, with the last eruption believed to have been approximately 400,000 years ago,Cornell University making it younger than Wolf.
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Yakima Fold Belt (thin purple lines with black diamonds) in context of major regional geological structures. Pale green is extent of the Columbia River Basalts. Thickest purple line is the OWL, thickest orange line corresponds to the craton edge in the shaded-relief map above. The Klamath-Blue Mountain Lineament (KBML, approximate location, extends to coast) is the southern edge of the marine basalts of Siletzia.
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It is about wide and deep and appears to have formed during a phreatomagmatic eruption. These vents lie at an elevation of about , making them among the highest vents of a Plinian eruption in the world. Slumps have buried parts of the amphitheatre. Dacitic dykes crop out within the amphitheatre and are aligned along a northwest–south trending lineament that the younger vents are also located on.
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Wolf Island is the remains of an extinct volcano that reaches a maximum above sea level, it is situated north west of the main Galápagos Island group on the Wolf-Darwin Lineament that extends from the Galápagos Platform to the Galápagos Spreading Center, a mid ocean ridge separating the Nazca and Cocos tectonic plates. Like its near neighbour Darwin Island, Wolf Island is upstream of the magma plume, in terms of plate movement, that forms the main Galápagos Islands and does not fit in with the formation of those islands. There are currently two theories on the formation of the lineament and therefore Wolf island: the first is that magma rising from the mantle plume forming the main Galápagos Islands has been channelled towards the Galápagos Spreading Center; alternatively there has been a separate rise in magma caused by stress in the ocean lithosphere by a transform fault.Blair et al.
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Tebenquicho together with other volcanoes such as Antofalla is a back-arc stratovolcano of the Puna. These volcanoes developed starting from 15-14 million years ago in response to a change in the subduction of the Nazca Plate beneath the South America Plate. These edifices are voluminous and volcanic activity on them long-lasting. Additionally, Tebenquicho together with Galan, Llullaillaco and some monogenetic volcanoes forms the so-called Archibarca volcano lineament.
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Palpana (from , ram) is a volcano in the Andes of Chile. It has a summit elevation of 6,040 metres above sea level and is part of the dividing range between Upper Loa River basin and Salar de Ascotán basin. Together with Inacaliri and Azufre, it forms a long volcanic chain constructed along the Inacaliri lineament. The volcano rises above an ignimbrite plain that in the area reaches an altitude of .
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There is a curious change of character of the OWL in the center of the CLEW where it crosses the roughly north-trending Hog Ranch--Naneum Anticline. West of there the OWL seems to follow a ridge in the basement structure, to the east it follows a gravity gradient, much like the Klamath-Blue Mountain LIneament (see below) does., p. 1258. The significance of all this is not known.
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S-type granite is only found for sure in the Eddystone Batholith in the most extreme north east. Away from the east the I-type granite proportion increases. Veins of gold were crystallised in the Mathinna- Alberton Gold Lineament, a line from Scottsdale to Blue Tier. The Scamander field originated from the edge of the Mount Pearson biotite adamellite-granite pluton, containing tungsten-molybdenum, tin-copper and silver-lead-zinc veins.
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The plants carry a dense canopy of simple leaves of a dull grey- green colour and a rigid, leathery lineament. Variation in terms of colour, shape, texture and arrangement is however considerable. Foliage colour varies from a greyish green to distinctly blue, and the leaf shape varies from lanceolate to obovate. New branches and foliage are covered in rust-brown scales (gland granules), while mature leaves may be hairy or glabrous.
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The earthquake originated in the Eastern Tennessee Seismic Zone, a fault noted for earthquakes of moderate magnitude. Faulting in the area is strike-slip-oriented, probably because of the Alabama-New York Lineament, which runs adjacent to the seismic zone. Several scientists believe that small earthquakes from the zone indicate the reactivation of deep, ancient faults. Alabama has seen roughly 20 earthquakes since the beginning of the 20th century.
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Such faulting is believed to be the surface manifestation of a deeper shear zone. Progression of ages of rhyolitic (silicic) lavas and calderas from McDermitt Caldera to Newberry and Yellowstone calderas (red circles: MC, NC, & YC). Numbers are ages in millions of years. KBML - Klamath–Blue Mountains Lineament, HLP - High Lava Plains, EDZ - Eugene—Denio Zone, BFZ - Brothers Fault Zone, SMF - Steens Mountain Fault, VF - Vale Fault, NNR - North Nevada Rift.
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The Bronnant Fault is a geological fault affecting the lower Palaeozoic rocks of the counties of Ceredigion and Pembrokeshire in West Wales. The feature is mapped over part of its length as the Bronnant Fault ZoneBritish Geological Survey 2006 Llangranog. England and Wales sheet 194. Bedrock and superficial deposits. 1:50,000 (Keyworth, Nottingham: BGS) and is closely associated with the Glandyfi Lineament, a similarly aligned zone of faulting and folding.
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Throughout the Paleogene, the same region witnessed both shale and carbonate formation in shallow water areas away from the Dinarides thrust belt. Paleontologists have gathered extensive fish fossils from the period out of the Bolca quarry close to Verona. Alpine uplift spurred tonalite, granodiorite, syenite and monzonite emplacement as batholiths and plutons, lasting into the Oligocene, as well as basaltic andesite intrusions. The Insubric Lineament sheared the Bregaglia batholith.
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Jemez Mountains near Jemez Pueblo The Jemez Mountains lie to the north of the Albuquerque Basin in the Rio Grande rift. They are a classic example of intracontinental volcanism and consist of a broadly circular ridge surrounding the famous Valles Caldera. The latter is the type location for resurgent caldera eruptions. The mountains lie on the intersection of the western margin of the Rio Grande Rift and the Jemez Lineament.
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The term 'Mazatzal orogeny' was applied to describe the Mazatzal Revolution by Lee Silver in 1965. The province extends from Arizona to Colorado south of a somewhat poorly defined boundary with the Yavapai Province that runs roughly along the Jemez Lineament. From there it continues along the southern margin of the Canadian Shield northeastward to Newfoundland. The southern boundary runs from northern Sonora to Newfoundland roughly parallel to the northern boundary.
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Some of the volcanic fields of the Basin and Range Province are within: Northwestern Nevada, the Modoc Plateau, Central Nevada, the Great Basin, Southwestern Nevada, the Mojave Desert, and the Long Valley Caldera region. Named ones include: Coso Volcanic Field, Mono Lake Volcanic Field, Marysvale Volcanic Field, San Juan volcanic field, Indian Peak, Central Colorado volcanic field, Jemez volcanic lineament, Mogollon-Datil volcanic field, Santa Rosa-Calico, and Boot Heel volcanic field.
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Activity at the summit continued during this time, forming the El Azufre sequence. This phase of edifice growth was interrupted by a major collapse of the western flank of Ollagüe. Debris from the collapse spread in the form of hummocks down the western slope and into an adjacent salt pan, splitting it in two. The occurrence of this collapse was perhaps facilitated by a major crustal lineament that crosses Ollagüe from southeast to northwest.
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Badger Mountain is a member of the Yakima Fold Belt, a series of topographical folds (or wrinkles) raised from tectonic compression. The Yakima Fold Belt extends from Interstate 90 near Vantage, Washington to the Columbia River near Wallula, Washington. The Yakima Fold Belt is a portion of the larger Olympic-Wallowa Lineament, which extends from near Port Angeles, Washington into northeastern Oregon.Field Trip Guide to the Columbia River Basalt Group Retrieved 31 May 2015.
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Geology map of Karioi, Pirongia, Kakepuku and Te Kawa Karioi is an extinct late Pliocene, low angle cone or shield volcano of the Alexandra Volcanic Group. It is the oldest and westernmost of the Alexandra lineament of volcanoes. Two million years ago Karioi was probably an ash cone, maybe double and at least 100 m higher than the present 756 m. It consists largely of basalt with andesite dikes, which mainly form the ridges.
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According to the United States Census Bureau, the city has a total area of , all of it land. Mt. Angel is in the Pudding River watershed. The town sits on the Gales Creek/Mount Angel lineament, and sits on the Mount Angel Fault, a northwest-trending geophysical structural zone. Activity along the fault caused the 1993 Scotts Mills earthquake which significantly damaged various structures in the town, in particular the parish church.
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By using Pioneer Venus, Goldstone, and Arecibo data, these regions have been interpreted as widespread superposed flows that originated from the source vents. Fracture zones and lineament belt segments that have been identified are said to represent the Beta-Eistla deformation zones of the region. Magellan SAR images have revealed that most of these surface units are composed of volcanic land forms. There is also Seymour crater that is associated with extensive crater outflow deposits.
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Chang Peak and Mount Waesche appear to be located outside of the Executive Committee Range volcanic lineament. The volcano erupted comendite, hawaiite and mugearite, with the former found at Chang Peak and the latter two at Mount Waesche proper; the parasitic cones have erupted a mugearite-benmoreite succession. The occurrence of rhyolite has also been reported. Phenocrysts at Chang Peak include aenigmatite, alkali feldspar, ilmenite and quartz and at Mount Waesche olivine, plagioclase and titanaugite.
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Fault activity has been widespread in the Puna with block faulting, but the volcanoes themselves are little affected by the faulting. However, the alignment of the centres may be linked to a north-south fault. A unique volcano La Pava-Ramadas is found north of Queva and has generated ash falls as far as the Subandean ranges 8.75 million years ago. The volcano was formed on top of the Calama–Olacapato–El Toro lineament.
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A pre-Isluga unit containing Cabay volcano, northeastern Carcanchuni and southern Cerro Blanco are not stratigraphically controlled. The Enquelga unit is the first Isluga unit proper. Further, Isluga and Tata Sabaya and some other volcanoes form a lineament which may coincide with the suture between the Chilenia terrane and the Arequipa-Antofalla block. Being about high over its base, Isluga has five craters, a main crater wide at the end of snowcovered summit ridge and underwent caldera collapse.
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Isluga's lavas are andesitic to trachyandesitic in composition with SiO2 contents between 56-61%. The andesites are porphyritic with more than half phenocrysts and high potassium content (2.7-3.6%), moderate aluminium and high magnesium, although some hornblendes have high Na/K ratios. The petrology of the Isluga lineament lavas indicates an origin either in 3-5% partial melting of the mantle, or by a 15% partial melting of a granite-containing mantle with subsequent fractionation of mafic components.
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The second important suture is called the Peri- Pieninic lineament, roughly copying the structure of Pieniny Klippen Belt. This important dislocation divides the Central and Outer Western Carpathians. Deeper under the sediments it constitutes the boundary between the Central Carpathian basement rocks and the foreland – the Bohemian Massif and East European craton (Podolia platform). Since the 1980s the dividing line has been considered the suture of the Vahic Ocean – the Eastern continuation of the Piemont-Liguria Ocean.
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Thanks to heavy erosion, lavas and eruption products are mostly found in peripheral parts of the edifice, while in the central area a deep-grounded crystalline core is exposed. A breach wide and long with an azimuth of 139° lies in the volcano, whose summit has a maximum slope of 25°. The volcano forms a lineament with Saxani and Isluga. The creeks named Qhamiña (Camiña) and on the western side Waywasi (Guayhuase) originate on the volcano.
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The mining district occurs along the intersection of two major regional structural features. A large anticline extends through the district, running in a north-northwesterly direction. The Lewis and Clark line – a series of strike-slip faults running across the Pacific Northwest – crosses this anticline, generally trending in an east-west direction. Within this mining district, the major structure of the lineament is the Osburn fault, which runs directly through the district’s most successful silver belts.
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Numerous mafic dykes intruded the basement in the late Permian and Early Jurassic, associated with the start of the separation of Africa from South America. These are part of the Central Atlantic Magmatic Province (CAMP). The northern Guiana Shield, including Guyana is separated from Southern Guiana Shield by ENE to NE trending Tumbes /Guayaquil - Tacutu Tectonic Lineament. This is a major regional pre-Cambrian shear zone / mega-shear which is believed to have been re-activated several times.
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Structures primarily found in the plains of Guinevere Planitia consist of wrinkle ridges, fractures and lineaments. Lineaments exhibit one dominant orientation of tectonic features. Extending through the plains of Guinevere is a deformation zone that is made up of discontinuous segments of lineament belts and ovoids that are referred to as the Beta-Eistla deformation zone. Other structural features are observed in coronae and coronae-like features as well as tesserae and other highly tectonized units.
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The basement is cut by faults and lineaments such as the Pampacolca Fault on the southern side of the volcano and the Pumaranra and Cerro Casulla lineaments, which trend southeastnorthwest and northeastsouthwest, respectively. One east–west lineament may have influenced the recent volcanism; the alignment of Coropuna with Sara Sara, Solimana and El Misti may indicate a tectonic control on the volcano in general. On the southern flank, Holocene normal faults have offset lava flows and streams.
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St. Helena, and several islands in the Cook-Austral volcanic lineament (e.g., Mangaia) are the type localities for HIMU ocean island basalts. The final mantle domain discussed here is the common composition that ocean island basalts trend toward in radiogenic isotopic multi-space. This is also most prevalent mantle source in ocean island basalts, and has intermediate to geochemically depleted 87Sr/86Sr, 143Nd/144Nd, and 176Hf/177Hf, as well as intermediate 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb.
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El Laco is part of the Cordón de Puntas Negras sector of the Central Volcanic Zone, directly south of that volcanic chain. It sits atop a quartzite and sandstone basement that was lifted from the seaground during the Acadian orogeny and is of Ordovician age. Later, Mesozoic and Cenozoic sedimentation occurred, which was then buried by Tertiary rhyolites. Two major volcanic lineaments cross in the El Laco area, including the so-called Calama-Olacapato-El Toro lineament.
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The source of seismic activity in the ETSZ is not known. The ETSZ is located far from edge of the North American continent and represents a mid- continent or intraplate earthquake zone. The known faults in the ETSZ are generally ancient; no known active faults reach the surface. Research published in 2010 indicates a correlation between the Eastern Tennessee Seismic Zone and the New York-Alabama Lineament and suggests that earthquakes in the seismic zone originate at depth in metasedimentary gneiss.
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Of these mountains, is more heavily eroded compared to the steep cones of Hasan and like is of early Pliocene age. It and to some degree Mount Hasan are also surrounded by a large depression. Additionally, Mount Hasan forms a volcanic lineament with and the Karapınar Field. The basement in Central Anatolia is formed by magmatic, metamorphic and ophiolitic rocks, the former of which are of Paleozoic to Mesozoic age; it crops out at scattered sites and in the Kirshehir and Nigde massifs.
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The area was intensely faulted and folded during the Caledonian Orogeny. Amongst structures from that period are the major lineament-forming Bala Fault / Tal-y-llyn Fault and the Pennal Fault along which the Dovey valley has been carved by water and ice. Numerous other faults ranging from north-south to NE - SW alignments are present throughout the district. Much of northern Snowdonia is characterised by large scale folds, the majority of which have a NE-SW aligned fold axis.
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Other volcanoes such as Cordon de Puntas Negras and the rim of the large La Pacana caldera farther north are also influenced by this lineament. To the west Socompa is bordered by the Sierra de Alameida (or Almeida), which farther north merges into the Cordon de Lila. To the east the high Salín volcano neighbours Socompa; other volcanoes in the area are the high Cerro Bayo and the high Socompa Cairis, all of which show evidence of glacial activity unlike the younger Socompa.
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A major regional tectonic lineament known as Culampaja passes through Pasto Ventura and the Vicuña Pampa volcanic complex lies east of the area. The volcanic rocks at Pasto Ventura are formed by basalt, andesite and basaltic andesite, and define a calc-alkaline suite. Lava flows and lava domes at Pasto Ventura have yielded phenocrysts of amphibole, olivine, plagioclase, pyroxene and xenocryst quartz; basement rocks are present as xenoliths and occur as blocks in maar deposits. Lithospheric delamination may be the cause of volcanism in the area.
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The fault seems to have been partly reactivated during the Neogene in the section between the Albertine and Gregory rifts, and along its southern extension towards the Indian Ocean. The reactivated section of the Aswa lineament connects the eastern and western branches of the East African rift system. It seems also to truncate the Nyanza rift, which extends ENE from Lake Victoria. The section of the Aswa Dislocation between the two rifts forms part of the boundary between the Somali Plate and the African Plate.
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The north west element was altered by the Tyennan Orogeny around . The Arthur Lineament was metamorphosed to phyllite, slate and schistose quartzite, The Burnie and Oonah Formation were folded in various ways, and the Rocky Cape Group and the Smithton Synclinorium developed cleavage texture. The Tyennan Orogeny corresponds with the first phase of the Delamerian Orogeny in South Australia and the Ross Orogeny in North Victoria Land, Antarctica. The Dove Granite intruded the Tyennan Block metamorphics with several small plugs in the north dated at .
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As Siletzia accreted it also jammed the existing subduction zone, halting subduction of the Farallon plate. This terminated the Laramide orogeny that had been uplifting the Rocky Mountains, and triggered the ignimbrite sweep, a wave of large-volume silicic magmatism that swept over much of western North America between 20 and 50 Ma.; . This undoubtedly affected the enigmatic and controversial Challis Arc (stretching from southeastern British Columbia to the Idaho Batholith, roughly parallel with the Olympic-Wallowa Lineament), but the details of this are unknown.; ; .
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Rifting began in the early Mesozoic, in the North Dobogrea-South Crimea Aulacogen, likely related to the strike-slip movement of the Tornquist-Teysseire Lineament. Ocean rifting through the Triassic separated Europe from the Preapulian Block. As the spreading of the Tethys Ocean continued, the Moesian Platform was rotated to the northwest and North Dobogrea experienced compression. The crust began to shorten and compress in the area of the Carpathian Mountains, as the Transylvanian nappe formations were obducted onto the edge of the continent.
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In these high temperature belts, the temperature peaked at 700°C and the pressure was 350 MPa, with a thermal gradient of 65 °/km. This same high temperature regime produced migmatite and S-type granite from the Ordovician sediments. Blueschist formed by intermediate to high pressure metamorphism is found in melange at Port Sorell and the Arthur Lineament in Tasmania, and Howqua Melange and Heathcote Melange in Victoria. Slate has been formed in other parts of the fold belt indicating intermediate pressure and low temperature.
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This volcanic field lies at the intersection of the Rio Grande Rift, which runs north-south through New Mexico, and the Jemez Lineament, which extends from southeastern Arizona northeast to western Oklahoma. The volcanic activity here is related to the tectonic movements of this intersection. NASA used the caldera in October to November 1964 and again in September 1966 to geologically train the Apollo Astronauts in recognizing volcanic features, such as ash flow tuffs, pumice air falls, and rhyolite domes. Notable geologist instructors included Roy Bailey.
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It rises northeast of the Gir Hills, near Dhari in Amreli district. Its course begins east-northeast along a lineament which runs parallel to the Narmada Fault, passes north of Palitana's hills, Shatrunjaya, then in a southeasterly direction past Talaja Hill, through a peninsula, before reaching the Gulf of Cambay, approximately north of Goapnath Point. It has two mouths, one situated approximately north of the point, and the other being an additional to the north. Situated eastward of the river's mouth is Sultanpur Shoal.
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After the formation of the caldera, between 6.9 and 6.8 million years ago the Abra Grande, Aguas Calientes and Río Grande stratovolcanoes grew in the caldera. Lava flows from Cerro Bayo and Cordón del Azufre have invaded the northwestern sector of the caldera. The Los Colorados caldera coalesces with the Lazufre structure along the Archibarca lineament and is associated with a major fault, the Pedernales-Arizaro overthrust. This fault may have favoured the formation of the Los Colorados caldera by facilitating the formation of a magma chamber.
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At the BFZ's eastern end, near the Steens Mountain fault, the zone of surface faulting turns slightly to the south-southeast (possibly due to rotation of Nevada), then follows the Northern Nevada Rift to form the Oregon-Nevada lineament, with a total length of over . Lavas associated with the Nevada Rift have been dated to 16.3 Ma (millions of years ago), close to the inception of basin-and- range faulting, but there is a suspicion that the rifting developed on an older strike-slip fault, possibly connected with the East Pacific Rise.. At its west end, just past the Newberry Volcano, the BFZ terminates at the north- striking Sisters Fault, part of the High Cascades geological province. But further south the Pliocene (<5 Ma) High Cascades volcanic trend is offset right-laterally about by the Eugene-Denio fault zone, and another by the McLoughlin zone.. At a possibly more fundamental level, the Brothers, Eugene- Denio, and McLoughlin zones, and possibly the Vale zone, all terminate near the Klamath - Blue Mountains Lineament (KBML; shortened and slightly misplaced on the map at right). The KBML is a prominent, long southwest-to-northeast- striking gravitational anomaly that crosses all of Oregon.
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A few hotspots are thought to exist below the North American Plate. The most notable hotspots are the Yellowstone (Wyoming), Jemez Lineament (New Mexico), and Anahim (British Columbia) hotspots. These are thought to be caused by a narrow stream of hot mantle convecting up from the Earth's core–mantle boundary called a mantle plume, although some geologists think that upper mantle convection is a more likely cause. The Yellowstone and Anahim hotspots are thought to have first arrived during the Miocene period and are still geologically active, creating earthquakes and volcanoes.
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The Central - Southern Uplands Terrane extends across the northernmost part of England. Its southern margin is the Iapetus Suture, south of which lies the Leinster - Lakesman Terrane which includes the Lake District and North Pennines. The majority of the rest of England and Wales north of the Variscan Front are considered to constitute the Avalon Composite Terrane. Central to this composite terrane is the triangular-shaped Midlands Microcraton; within it, the north-south aligned Malvern Line (or 'Malvern Lineament') divides the Wrekin Terrane in the west from the Charnwood Terrane in the east.
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Later in the Paleogene, another phase of orogeny affected the Pieniny Klippen Belt. It squeezed the former nappe stack and the rocks of different rheology (competent limestones, soft flysch, and marls) were deformed in different ways, which caused the rupture of more dense rock and ductile deformation of the less dense rock. Complicated arrangement of particular tectonic units was later affected by strike-slip motion in the area of the Peri-Pieniny Lineament in the Miocene. Consequent erosion dissected the rigid limestone tectonic lenses to the shape of protruding klippes (e.g.
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Volcanic activity in the area occurred between 15 and 10 million years ago, and Cerro San Antonio, a heavily eroded 3 million years old Miocene volcano with a westward-opening collapse scar, lies just north of Uturuncu. Other volcanoes from east counterclockwise to west are the Cerro Panizos caldera, Cerro Lípez, Suni K'ira and Quetena volcanoes as well as many more minor volcanic centres. Many of them are formed along northwest-southeast trending lineaments such as the Lipez-Coranzuli and Pastos Grandes-Cojina lineament that passes through Uturuncu.
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Hydrothermally altered rhyolites contain rutile and secondary silicates in veins. All products are porphyritic, including the late andesites which contain phenocrysts of hornblende and plagioclase with smaller amounts of biotite, clinopyroxene, iron oxides and orthopyroxene. Based on crystal analysis, the rhyolites were stored at pressures of and temperatures of . The volcano is situated at the point where the main volcanic arc intersects the Calama–Olacapato–El Toro lineament, a fault zone that has formed over fifteen million years a number of volcanic structures including lava domes, stratovolcanoes and monogenetic scoria cones.
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Similar igneous-cored ranges of the Colorado Plateau, including the Henry Mountains, Abajo Mountains and La Sal Range, formed ca. 31 to 20 million years ago, making them distinctly younger than the late Cretaceous intrusions of the Carrizo Mountains. Radiometric ages of igneous intrusions in Sleeping Ute Mountain are essentially identical to those of the diorite intrusions in the Carrizos. Both the Carrizo Mountains and Sleeping Ute Mountain are located along the southwest extension of the Colorado Mineral Belt, a 250-mile long lineament characterized by igneous rocks associated with abundant ore deposits.
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It includes three zones. The Zona Transveral is in the central sub-province between the Pernambuco Shear Zone and the São Francisco Craton, displaying 2.2 billion year old gneiss, a suite of metavolcanic, metasedimentary and metaplutonic rocks as well as pluton formations from 640 to 540 million years ago. Uranium-lead dating has revealed two periods of acid magmatism in central Brazil, which produced the Goias tin province in granite and rhyolite. The Pernambuco Shear Zone, or lineament, is a steeply-dipping ductile shear zone formed 600 million years ago during the Brasiliano orogeny.
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The Prince Regent Fault is a major fault that trends along the east coast of Somerset Island. It forms the southwestern boundary of the Lancaster Aulacogen and is west of the inferred Brodeur Peninsula Fault, which presumably trends along the northwest coast of Baffin Island's Brodeur Peninsula. The main evidence of the Prince Regent Fault is the straightness of Somerset Island's east coast, but the southern end of this fault also connects with a lineament that is a known fault on land. A series of fracture zones are present in the Labrador Sea.
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The Cribarth Disturbance is a geological structure forming a lineament which stretches across south Wales from Swansea up the Swansea Valley then northeastwards to Brecon and beyond. It consists of both a series of faults and associated folds which were active during the mountain-building period known as the Variscan orogeny. This line of weakness probably featured in the earlier Caledonian Orogeny and perhaps reflects a more ancient line of weakness in the basement rocks. It is also known (in part) as the Tawe Valley Disturbance or the Swansea Valley Disturbance.
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View south-west along the fault line with Talyllyn Lake in the valley bottom The Bala Fault is a SW-NE trending geological fault in Wales that extends offshore into Cardigan Bay. In the offshore area it is a major normal fault and forms the bounding structure to the Cardigan Bay Basin, with a fill including about of Lias Group. Onshore it is responsible for the lineament which runs through Bala and south of Cadair Idris to the coast at Tywyn. At its northeastern end it links to the similarly orientated Llanelidan Fault.
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Many of these lineaments may be faint secondary-crater chains or gouges; others may represent traces of an ancestral structural pattern that partly controlled the excavation of the craters and basin. The lineaments may have been enhanced or preserved by the gentle upwarping of this region of Tolstoj ejecta discussed above. The largest lineament, which marks the northwest limit of recognizable Tolstoj ejecta, is a subdued scarp some 450 km long. Rejuvenation of earlier faults or fractures by subsequent impacts probably occurred throughout the history of the planet.
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These fractures may have provided egress for the eruption of the oldest plains material during the period of heavy bombardment. Also about this time other structural lineaments developed, possibly as a result of stresses induced by tidal spin-down from a more rapid rotation rate (Burns, 1976; Melosh, 1977; Melosh and Dzurisin, 1978). The major east-west lineament trend in this polar region (noted in previous section) conforms to a prediction of Melosh (1977) for the orientation of normal faults. However, no unambiguous evidence for tensional faults occurs in the Bach quadrangle.
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The Laxmi Ridge, the larger of these, is made of continental crust and formed during the Seychelles-India breakup. East of the Laxmi Ridge in the Laxmi Basin, the Panikkar Ridge is made of stretched continental crust and has a similar tectonic history. In contrast, the Palitana Ridge north of the Panikkar Ridge probably represents an extinct spreading centre and on the nearby shelf and slope a lineament, known as the Prathap Ridge Complex, is similarly made of oceanic crust and both are probably leftovers from the India–Madagascar breakup.
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The press release noted that a high grade deposit at Carheil Lake, less than from the Lac Rainy project area, had yielded samples of 35.49% Cg and 40.67% Cg. The Carheil Lake deposit is on the west shore of the south part of the lake. The graphite was found in a structural lineament that runs roughly north-south for about . A report by the same company in May 2019 stated that they had drilled 17 holes along the formation for a length of about and confirmed eastern and western extensions of the Carheil Graphitic Zone.
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The rhyolitic rocks themselves are representative of explosive volcanic centres to the west of this site and beyond the Church Stretton lineament. There is a clear distinction between the tuffaceous rocks of the Uriconican Volcanics (dark brown/black/grey) and the intrusive granophyre which is pink. The relationship between the Ercall Granophyre and the Uriconian is also clearly evident as the Granophyre intrudes the Volcanic rocks and is therefore younger. The Ercall Granophyre is overlain by shallow dipping Cambrian rocks (in relation to the steeply dipping Uriconian volcanics) which contain Atdabanian fossils.
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Lake Alamosa existed for about 3 million years, from the Pliocene to the middle Pleistocene. Rocks in the San Luis horst stretch across the entire Alamosa Basin and together with 4.8-3.7 million years old basaltic lava flows of the Taos Plateau blocked the basin from draining to the south. Tectonic uplift of the Jemez lineament, tectonic subsidence of the Lake Alamosa area and the emplacement of these lava flows may have obstructed former drainages, but evidence of prior southwards drainage has been found only recently. South of Lake Alamosa an even older lake, Lake Sunshine, occupied the Sunshine Valley during the Pliocene.
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The OFZ (also called the Trans-Idaho Discontinuity) is a local segment of a larger structure that has only recently been recognized, the Great Divide Megashear.. East of the WISZ this turns to the southeast (much as the OWL may be doing past the Wallula Gap) to follow the Clearwater fault zone down the continental divide near the Idaho--Montana border to the northwestern corner of Wyoming. From there it seems to connect with the Snake River--Wichita fault zone, which passes through Colorado, and Oklahoma.,; . A few sources have described this general trend the Olympic-- Wichita Lineament (e.g.
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It extends north northeast to Phillip Island, Victoria, and also south 40 km to just off the west coast of Tasmania stopping at the Braddon River Fault In the Rocky Cape Block west of Wynyard and north of Granville Harbour, the Precambrian rocks consist of the Rocky Cape Group from the Stenian period, with Cowrie Siltstone, Detention Subgroup, Irby Siltstone, and Jacob Quartzite. The sequence covers most of the block and is over 5700 metres thick. Currents travelled either northwesterly or southeasterly. The metamorphic belt titled the Arthur Lineament forms the limits of the Rocky Cape Group to the south east.
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The Brothers Fault Zone (BFZ) is the most notable of a set of northwest- trending fault zones including the Eugene-Denio, McLoughlin, and Vale zones that dominate the geological structure of most of Oregon. These are also representative of a regional pattern of generally northwest-striking geological features ranging from Walker Lane on the California-Nevada border to the Olympic-Wallowa Lineament in Washington; these are generally associated with the regional extension and faulting of the Basin and Range Province, of which the BFZ is considered the northern boundary. (USGS Quaternary Fault and Fold database). The relationships with other features is complex.
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Larger earthquakes like the 1936 State Line earthquake are not uncommon along the Olympic-Wallowa Lineament, a series of faults stretching from Port Angeles, Washington to the Wallowa Mountains in northeast Oregon. Another earthquake estimated near a magnitude 6 struck the Walla Walla valley in 1882. The earthquake occurred in the Touchet Ridge, a spur leading west off the Blue Mountains that is known as the Horse Heaven Hills west of the Wallula Gap. There is both the old fault along the ridge as well as a newer fault leading from the ridge into the valley.
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Instead, the common local name of "Bavarian Forest" is used for the entire area of the low mountain range on the German side, as the term "Bohemian Forest" has become synonymous with the areas in the Czech Republic. A distinction is only made between the Anterior Bavarian Forest and the High Bavarian Forest, with the lineament of the Bavarian Pfahl being regarded as the boundary line between them. In the north-south direction, a distinction is made between the Upper and Lower Forest. The Bavarian Forest is the rump of a Palaeozoic mountain chain, whose bedrock is classified as Late Proterozoic to Silurian.
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The southern boundary is somewhat poorly defined, possibly because it corresponds to a shallow relic subduction zone, but runs roughly along the Jemez Lineament. Individual island arc terranes accreted to Laurentia during the Yavapai Orogeny include the Elves Chasm block in the Grand Canyon, Green Mountain, Dubois-Cochetopa, Irving Formation, Moppin-Gold Hill, and Ash Creek- Payson. The latter includes the Payson Ophiolite. Quartzite-rhyolite successions associated with extensional basins include the Vadito Group and Hondo Group in New Mexico and the Mazatzal Group in Arizona, deposited during the transition from the Yavapai to the Mazatzal orogens at 1700 Mya.
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The lower two units coincide with the Lower and Middle Omingonde Formation, the upper two units make up the Upper Omingonde Formation. Thicknesses and architectural style of the units vary laterally and are influenced by syn-sedimentary tectonic activity of the Waterberg-Omaruru Lineament. The full range of facies is best developed in the Mt. Waterberg area, whereas farther west in the Erongo Region more proximal facies are favored. This proximal facies association has been termed the Krantzberg Formation in the western, northern and eastern Erongo area, and interfingers with the Lions Head Formation towards the southeastern Erongo Region.
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At Cribarth, Variscan movement on this Caledonoid feature has given rise to a couple of folds in the limestone and overlying Twrch Sandstone from which the present landform has subsequently been carved, in part by glacial action. The southernmost lineament is the Neath Disturbance which runs ENE from Swansea Bay up the Vale of Neath and into the park at Pontneddfechan. The limestone is tightly folded here at Bwa Maen (Welsh: 'stone bow') and again at Moel Penderyn, through which it next passes. It passes beneath Pontsticill Reservoir, across the top of Dyffryn Crawnon and then down the shallow Onneu valley to Crickhowell.
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Volcanism of the Altiplano is caused by the collision between the Nazca Plate and the South America Plate. Various phenomena caused a thickening of the crust in the Altiplano region; such thickening however postdates volcanic activity at Luingo and thus the volcano was unaffected by its chemical effects. Between 8 and 3 million years ago the volcanic arc moved towards the east due to subduction eroding the forearc and 6 million years ago voluminous ignimbritic volcanism commenced. Since 3 million years ago, ignimbritic volcanism is aligned both along the Chile-Argentina border and a lineament including Galan, Cerro Blanco and Incapillo.
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The 38th parallel structures, also known as the 38th parallel lineament,Gillman, Joe (ed.), Association of Missouri Geologists Field Trip Guidebook, 51st Annual Meeting, Rolla, Missouri, October 1–2, 2004, 2004, Missouri Department of Natural Resources, Geological Survey and Resource Assessment Division, p. 15 are a series of circular depressions or deformations stretching across southern Illinois and Missouri and into eastern Kansas, in the United States, at a latitude of roughly 38 degrees north. Rampino and Volk (1996) postulated that these structures could be the remains of a serial meteorite strike during the late Mississippian or early Pennsylvanian periods (320 ± 10 Ma).Rampino & Volk, 1996, p.
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Past the Hite Fault System the OWL enters a region of geological complexity and confusion, where even the trace of the OWL is less clear, even to the point where it has been suggested that both the topographic feature and the Wallula fault are terminated by the Hite fault., p. 2-17. The original topographic lineament as described by Raisz is along the scarp on the northeast side of the Wallowa Mountains. However, there is a sense that the trend of the faulting in that area turns more to the south; it has been suggested the faulting associated with the OWL takes a large step south to the Vale Fault Zone, .
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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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Whether formed far offshore as seamounts, or close inshore by a slab window, the Siletzian basalts were laid down on a subducting oceanic plate: the Siletz terrane on the Farallon plate, and the Crescent terrane most likely on the adjoining Resurrection plate (previously broken away from the Kula plate, which had previously broken away from the Farallon plate). In both cases the Siletzia mass was drawn toward the subduction zone, which possibly ran diagonally across what is now Washington, approximately at the position of the Olympic-Wallowa Lineament., figure 5; see also . This would be the Challis subduction zone, but there is some question about it.
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Mafic inclusions occur in some eruption products. The basement of the region is formed by various formations of Precambrian to Tertiary age, some of which crop out around the volcano. This basement is cut by various faults, which mark an uplift that forms the Creston Alto de La Aguada east of Chimpa volcano, as well as the Calama-Olacapato-El Toro lineament and associated faults which runs south of the Chimpa volcano and has localized the formation of volcanoes along its path and also influenced the activity of Chimpa. Cerro Rumio is another volcano which crops out south of Chimpa and is in part buried by Chimpa's deposits.
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Examples of mass movement are not common in Snowdonia but there is a concentration along the glacially excavated Bala lineament through Talyllyn. The largest is that which originates on the steep northwest slopes of Graig Goch and which has resulted in a mass of debris up to 30m high covering the otherwise flat floor of this trough and behind which is the lake. There are further smaller examples which form Bwlch Cyfyng southwest of Abergynolwyn and on the southeastern slopes of Mynydd Gwerngraig east of Cadair Idris. A further mass of slipped material is recorded beneath the peak of Pen yr Helgi Du at the head of Cwm Eigiau.
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Theoretical studies by Melosh (1977), based on observations recorded by Dzurisin (1978), suggested that tidal spin-down combined with core or lithospheric contraction could explain many of the tectonic features of Mercury. The scarps occurring in the polar regions do appear to be the result of thrust faulting, which substantiates the suggestion that contraction occurred concurrently with spin-down. Linear structures (other than some ridges) are thus interpreted to form as a result of these two active processes. Fracture and lineament patterns around the Caloris basin suggested to Pechmann and Melosh (1979) that Mercury's despinning period began before global contraction started and ended during the contraction's early phases.
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Ch'iyar Qullu (Aymara ch'iyara black, qullu mountain, "black mountain", also spelled Chiar Kkollu) is a volcanic centre in Bolivia. It is located in the Oruro Department, Ladislao Cabrera Province, Salinas de Garci Mendoza Municipality, northeast of Salinas de Garci Mendoza, near a maar named Jayu Quta ("salt lake"). It is a sill formed from primitive phyric alkali basalt that closely resembles ocean island basalt in composition and now appears as a hill. The rocks contain augite and olivine and the eruption site coincides with a local lineament and is of Miocene age, with dates of 22.51±0.45 mya by Ar-Ar dating and 25.2±0.5 mya by K-Ar dating.
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BFZ, EDFZ, and MFZ are the Brothers, Eugene-Denio, and McLaughlin fault zones. It is the central portion of the Olympic-Wallowa Lineament, referred to as the Cle Elum-Wallula deformed zone (CLEW), constising of a series of generally east-trending narrow asymmetrical anticlinal ridges and broad synclinal valleys formed by folding of Miocene Columbia River basalt flows and sediments. In most parts of the belt the folds have a north vergence (Columbia Hills' south vergence is an exception) with the steep limb typically faulted by imbricate thrust faults. Fold lengths range from 1 km to 100 km with wavelengths from several kilometers to 20 km.
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Volcanism in southern Peru occurs as part of two distinct volcanic systems, the stratovolcanoes of the Western Cordillera and the Altiplano volcanoes which are typically small systems with surface areas of less than . Of these Altiplano volcanoes, a number of them are potassium enriched or ultrapotassic rocks and are arranged along various lineaments. One of these lineaments is associated with the Cusco and Vilcanota faults which separate the Altiplano into a western and eastern portion. Quimsachata is located along this central and still active lineament, whereas the other two lineaments on each side of the fault system were active in the Oligocene and Miocene.
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The Caja del Rio plateau is a monogenetic volcanic field, which includes approximately 60 cinder cones, spatter cones, and basalt outflows. The volcanism can be explained by the field's location, which is very close to the intersection of the Rio Grande Rift and the Jemez Lineament. The Rio Grande Rift is a result of extensional, (or divergent) tectonic forces exerted upon the American Southwest. This feature runs southward from the vicinity of Leadville, Colorado, through the entire state of New Mexico, through the vicinity of El Paso, Texas, and into Chihuahua, Mexico. The Rift began forming approximately 30 million years ago during the late Oligocene Epoch.
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The suture resulting from closure of the Tornquist Sea may be seen in eastern England and the Lake District as an arc of igneous rocks belonging to the Ordovician. The volcanic series in eastern England, the Ardennes and the Northern Phyllite Belt originated between the Tornquist Sea and the Rheic Ocean during the Ordovician and Silurian. Where Baltica and Avalonia finally collided is now a suture known as the Teisseyre-Tornquist Line or Zone; named after its discoverer, Polish geologist Wawrzyniec Teisseyre and German geologist Alexander Tornquist. This lineament still marks the transition between, on one hand, the East and North European Pre-Cambrian Craton and, on the other hand, the West European and Mediterranean Palaeozoic Orogenes.
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The Neath Disturbance is a geological structure which stretches across south Wales from Swansea Bay northeastwards as far as Hereford in western England. It consists of a series of both faults and associated folds which were active during the mountain-building period known as the Variscan orogeny. This line of weakness probably featured in the earlier Caledonian Orogeny and perhaps reflects a more ancient line of weakness in the basement rocks.Howells, M.F. 2007 'British Regional Geology: Wales' Keyworth, Nottingham, British Geological Survey The Disturbance gives rise to a lineament crossing the region, that is to say that it is responsible for a number of significant landscape features along its 100 km length.
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The Transamazonian orogeny was a mountain building event in the Paleoproterozoic, affecting what is now the São Francisco Craton and Guyana Shield. During the orogeny from 2.14 to 1.94 billion years ago two small Archean proto-continents—including the greenstone belt-dominated Gavião Block and the calc-alkaline charnockite and enderbite-dominated Jequié Block—collided. The Contendas-Jacobina Lineament represents a suture zone where the collision occurred and the Gavião Block partially subducted under the Jequié Block. At the same time, another small continental fragment, the Serrinha Block, may have collided as well and was extensively reworked and metamorphosed, with orthogneiss and migmatite reaching amphibolite-grade on the sequence of metamorphic facies.
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This structure gives rise to a series of landscape features along its length, not least the steep northwest-facing scarps of the hills and ranges mentioned above. Indeed, the feature can be seen as a significant lineament in aerial and satellite views of Wales.British Geological Survey 1:50,000 map sheets 196 'Builth Wells', 212 'Llandovery', 213 'Brecon' and 230 'Ammanford' & accompanying sheet explanationsOrdnance Survey Explorer map OL12 'Brecon Beacons National Park: western area' The Steep Belt effectively marks the southeastern edge of the intensely folded region of the Caledonian Orogenic Belt in central Wales. A series of major folds and faults affect the Ordovician and Silurian rocks to its northwest whilst folding and faulting of the Devonian rocks to its southeast is much more subdued.
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Haruj is not located close to a plate boundary. Rather, volcanism there and in other African volcanic fields which are located on top of crustal domes, has been explained by the presence of hotspots, but in the case of Haruj a mantle plume is considered unlikely. Alternatively, volcanism at Haruj may be the consequence of the intersection of three geological structures of Paleozoic to Tertiary age and melting of the shallow mantle, or of the rifting process of the Sirte Basin. Wau an Namus is sometimes considered to be part of the field, other volcanic fields in Libya are Gharyan, Gabal as Sawada, Gabal Nuqay and Tibesti some of which belong to a long line known as the Tibesti lineament.
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Major geographical features near Cameroon line The Cameroon line bisects the angle where the coast of Africa makes a 90° bend from the southern coast along the west of the Congo craton and the western coast along the south of the West African craton. The coastline roughly corresponds to the coast of the Borborema geological province of northeastern Brazil, which began to separate from this part Africa around 115 million years ago. The Central African Shear Zone (CASZ), a lineament that extends from the Sudan to coastal Cameroon, runs under the continental section of the Cameroon line. It is visible in the Foumban Shear Zone, which was active before and during the opening of the South Atlantic in the Cretaceous period.
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Location of SCF and related faults in the North Cascades. __NOTOC__ The Straight Creek Fault (SCF) is the principal north-south strike-slip fault in the state of Washington, with a minimum of 90 kilometers (54 miles) of right- lateral offset, and a major geological structure in the North Cascade mountains, where it separates the pre-Cenozoic igneous and metamorphic rocks of the North Cascades on the east from the younger accreted terranes on the west. The SCF can be traced from its junction with the Olympic-Wallowa Lineament (OWL) near the town of Easton northward into British Columbia, where it joins the Fraser River Fault system; the combined system (over 570 km [340 miles] long) is known as the Fraser--Straight Creek Fault system (FSCF).; ; ;; (chs.
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Seeking to explain the observed clockwise paleorotation, and noting that Siletzia appeared to have rotated as a rigid block, proposed two models. First was rotation about a southern pivot in contact with the Klamath Mountains. This has various problems, especially because at the northern end sediments and even boulders from the continent are found at the base of the Crescent Formation, showing that it was near the continent from the beginning.. In the second model (subsequently refined by ), Siletzia was originally adjacent to the Olympic-Wallowa Lineament, then rifted from the continent and rotated about a northern pivot near the Olympic Peninsula. Because sediments also show the Klamaths in close contact from the start, this requires the Klamaths to have moved with Siletzia.
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The straightness of its surface trace suggests the LRF has been a strike-slip fault.; . In these respects the LRF is very similar to the Devils Mountain Fault, which can be traced due west from near Mount Vernon to a point just south of Victoria.. Near the Leech River, where the Survey Mountain fault marks the eastern limit of the Leech River Complex,. the LRF and the lineament it follows make a sharp turn to the south (heading S70°E) to run down the Goldstream River, past Victoria and into the Juan de Fuca Strait.. Such sharp turns are geometrically impossible for individual strike- slip faults, but the southeast-striking Goldstream arm of the LRF parallels the cross-cutting Survey Mountain fault.
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The relationship of the Seattle Uplift with other neighboring blocks, and the nature of the faults between them, is not well known. If tectonic strain is from the south, and therefore perpendicular to the Seattle and Tacoma Faults, the motion on them should be entirely dip-slip (vertical). If tectonic strain is from the south-west (see adjoining diagram), perpendicular to the Rosedale monocline, and also to the Olympia Fault (south-west boundary of the Tacoma Basin) and South Whidbey Island Fault (north-east of the Seattle Basin), both of which are parallel to the Rosedale monocline (and also to the Olympic-Wallowa Lineament, whose significance here is not known), then there should be some component of left- lateral strike-slip motion on parts of the Seattle and Tacoma faults., p. 24.
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All of these are carved into "recent" (less than 18,000 years old) glacial deposits, and it is difficult to conceive of how these could be controlled by anything other than a recent glacial process. Yet the same orientation shows up in the Brothers, Eugene-Denio, and McLoughlin fault zones in Oregon (see map, below), which are geological features tens of millions of years old, and the Walker Lane lineament in Nevada. Likewise to the east, where both the OWL and the Brothers Fault Zone become less distinct in Idaho where they hit the old North American continental craton and the track of Yellowstone hotspot. But some 50 miles to the north is the parallel Trans-Idaho Discontinuity, and further north, the Osburn fault (Lewis and Clark line) running roughly from Missoula to Spokane.
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The primal Neckar started off as an escarpment riverlet due to the slow rise of the Black Forest and the connected slow erosive retraction of the South German Scarplands.Historic routes of the Neckar at the mouth For a long time it flowed on the high plains of the different Gäu Plateaus created through the hard chalks of the Muschelkalk. At Horb the river was redirected to the northeast due to the rift structure of the so-called Swabian Lineament, which lies roughly parallel to the escarpment of the Swabian Jura. Following that the Neckar cut into the Muschelkalk plateau between Rottweil and Rottenburg as well as the younger Keuper and Jura layers in the northeast, and created narrow water gaps in the area of the morphologially hard chalks and sandstones .
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Together with the neighbouring Laguna Amarga caldera and Laguna Escondida caldera Wheelwright forms an alignment of Miocene-Pliocene calderas; the latter caldera in part overlaps with the Wheelwright caldera. The region coincides with a lineament of volcanoes which forms the southern margin of the volcanically active Central Andes; south of this margin the Nazca Plate subducts beneath the South America Plate at a shallow angle and Quaternary volcanism is absent. The oldest outcrops are found in the Cordillera Claudio Gay mountain range just west of Wheelwright; these outcrops are Paleozoic sediments and volcanic rocks. Volcanic arc volcanism has been ongoing in the region since 180 million years ago and migrated eastward during that time, but the modern arc developed 26 million years ago when the Farallon Plate broke up.
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The Southern Whidbey Island Fault (SWIF), running nearly parallel to the OWL from Victoria, B.C., southeast to the Cascade foothills to a point northeast of Seattle, is notable as the contact between the Coast Range block of oceanic crust to the west and the Cascades block of pre-Cenozoic continental crust to the east.. It appears to connect with the more southerly oriented right-lateral Rattlesnake Mountain Fault Zone (RMFZ) straddling Rattlesnake Mountain (near North Bend), which shows a similar deep-seated contact between different kinds of basement rock.DGER Geological Map . At the southern end of Rattlesnake Mountain - exactly where the first lineament of the OWL is encountered - at least one strand of the RMFZ (the others are hidden) turns to run by Cedar Falls and up the Cedar River. Other faults to the south also show a similar turn,DGER Geological Map .
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Volcanism is widespread in the western United States and occurs in various forms at various places. Among the better known are the Cascade volcanoes created by subduction off the western coast of North America, which include the caldera of Mount Mazama (created by a large eruption in the early Holocene) as well as stratovolcanoes such as Mount St. Helens and mafic volcanic fields. Other volcanic centres in the United States are those associated with Yellowstone Caldera and Snake River Plain, those along the margins of the Colorado Plateau, volcanoes linked to the Rio Grande Rift and Jemez lineament, and finally volcanoes in the western Basin and Range Province such as the Cima volcanic field. Generally, volcanic activity was widespread in the dry regions of the western United States during the Tertiary and Quaternary, forming several volcanic fields.
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Lava Fields and sandstone bluff The lava flows, cinder cones, and other volcanic features of El Malpais are part of the Zuni-Bandera volcanic field, the second largest volcanic field in the Basin and Range Province. This volcanically active area on the southeast margin of the Colorado Plateau is at the intersection of the Rio Grande Rift Basin, with its deep normal faulting, and the ancient Jemez Lineament. These two features provide the crustal weaknesses that recent magmatic intrusions and Cenozoic volcanism are attributed to. The rugged pāhoehoe and ʻaʻā lava flows of the Zuni-Bandera eruptions (also called the Grants Lava Flows) filled a large basin, created by normal faulting associated with the Rio Grande Rift, between the high mesas of the Acoma Pueblo to the east, Mt. Taylor to the north, and the Zuni Mountain anticline to the northwest.
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It coincides with the southern boundary of the Columbia Embayment (the Olympic-Wallowa Lineament in Washington being the northern boundary), a region noticeably lacking in pre-Tertiary bedrock. Aside from aligning with the northwestern edge of several terranes that have accreted to the North American continent (such as the Klamath Mountains on the southern coast of Oregon, and Blue Mountains Province just north of the BFZ), the KBML has no apparent surface manifestation; it is believed to reflect a deeper structure, possible a pre- Tertiary continental margin.. The BFZ is the northern edge of the Basin and Range Province, a region of northwest directed extension, wherefore the BFZ also accommodates the offset with the Blue Mountains Province. It does this not by through-going strike-slip faulting (such as with the San Andreas fault to the south) but by a series of hundreds of en echelon normal faults somewhat crosswise to the zone itself.; says thousands of faults.
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Melosh (1977) predicted that normal east-trending faults would form in high Mercurian latitudes as a result of slight crustal shortening. His predicted faults may be represented by a generally east-northeast-trending scarp and a lineament that cut across intermediate plains material and the crater Jókai between the 125° and 155° meridians. The north pole is too close to the terminator to detect the presence or absence of a “polygonal arrangement without preferred orientation,” as predicted by Melosh and Dzurisin (1978, p. 233). Arcuate and radial lineaments that might result from tectonic adjustments of the Mercurian crust, following excavation of very large multiring impact basins such as the one postulated under Borealis Planitia (Boyce and Grolier, 1977), were not unambiguously identified in the Borealis region. On one hand, some ridges on the surface of the smooth plains material in Borealis Planitia may be of structural (internal) origin; this type of ridge elsewhere on Mercury has been ascribed to compression and a slight shortening of the crust (Melosh, 1977; Melosh and Dzurisin, 1978).
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Jacob's Island was immortalised by Charles Dickens's novel Oliver Twist, in which the principal villain Bill Sikes dies in the mud of 'Folly Ditch'. Dickens provides a vivid description of what it was like: > ... crazy wooden galleries common to the backs of half a dozen houses, with > holes from which to look upon the slime beneath; windows, broken and > patched, with poles thrust out, on which to dry the linen that is never > there; rooms so small, so filthy, so confined, that the air would seem to be > too tainted even for the dirt and squalor which they shelter; wooden > chambers thrusting themselves out above the mud and threatening to fall into > it – as some have done; dirt-besmeared walls and decaying foundations, every > repulsive lineament of poverty, every loathsome indication of filth, rot, > and garbage: all these ornament the banks of Jacob's Island. Dickens was taken to this then-impoverished and unsavory location by the officers of the river police, with whom he would occasionally go on patrol. Illustrator George Cruikshank depicts Bill Sikes attempt at escape from his rooftop in Oliver Twist.
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A large portion of the slippage between the Pacific and North American plates is accommodated in the Eastern California Shear Zone (ECSZ), resulting in many large earthquakes even within the limited span of the historical era.. Most notable of these earthquakes is the 1872 Owens Valley earthquake, With an estimated magnitude of 7.4 (preferred; other estimates range as high as 7.9.), this earthquake is believed to be the greatest earthquake on record not only for California, but for all of the western United States.. In March 1946 an . earthquake struck near Walker Pass (crest of the Sierra Nevada, due west from Ridgecest), with aftershocks continuing for nearly a year.. The 1952 Kern County earthquake (, ), considered the biggest earthquake to hit California since the 1906 San Francisco earthquake,. occurred on the White Wolf fault south of Bakersfield, and likely connected with the Walker Pass earthquake via the Scodie Lineament.. At the southern end of the ECSZ the 1992 Landers earthquake, at magnitude () was also the strongest earthquake in California since 1906. It was followed by a () quake on a nearby fault, the 1999 Hector Mine earthquake.
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A major problem for a southern pivot is that it implies rotation during accretion, while most studies indicate that most or all of the rotation occurred after the presumed accretion . A key piece of evidence is that the Crescent Formation is laid over sediments (the Blue Mountain unit) derived from the continent, including boulders of quartz diorite some 65 million years old. This was previously interpreted as requiring the Crescent Formation to have formed close to the continent.. See also and . However, new high-precision U-Pb dating shows that the overlying basalts are older, and therefore the Blue Mountain unit was not overlaid by the basalts, but thrust under them at a later date.. Such under-thrusting implies that the northern end of Siletzia was initially further away from the continent, and permits radial motion about a more southerly or more easterly pivot near the Washington-Oregon border, as recently suggested.. This model has Siletzia forming on the continental margin along what is now the Olympic- Wallowa Lineament (OWL; a zone of topographical features of unknown age and tectonic significance), with the southern end of Siletzia and the Klamath Mountains (joined to Siletzia) near the Idaho Batholith in central Idaho.
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