The Murrieta Hogbacks are Miocene basalt capped granitic hogbacks located in northeastern Murrieta on the southern end of the Temescal Mountains of Riverside County, California.
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Hogbacks are recumbent stone monuments found across Scotland and Northern England that date to the 10th – 11th centuries AD; the term ‘hogback’ was established prior to 1885 to describe the characteristic curved ridge of the monument. Hogbacks are often decorated with rows of tegulation on the broad faces and each end often sports stylised or naturalistic beasts, though there is substantial variation on these traits from monument to monument. The tegulation has led many to argue that hogbacks are meant to emulate a house-shape, specifically Scandinavian long houses. Five hogbacks are housed at Govan Old, the largest collection of hogbacks in Scotland; four of these are the largest known hogbacks in all of Great Britain.
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The smallest of the hogbacks (SM 2, ECMS 2, Lang 1) is the best preserved and exhibits the most decoration; it has been suggested that this style has similarities to sculpture in Cumbria . Two of the hogbacks have each been recut to resemble a single beast, though it is unclear when this took place. Three of the hogbacks have concave tegulation, while the other two exhibit straight-sided ‘shingles’.
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Engel, GEOLOGY AND MINERAL DEPOSITS OF THE LAKE ELSINORE QUADRANGLE, p. 14 The Murrieta Hogbacks are the southeasternmost heights of the range, overlooking the Warm Springs Creek Canyon.
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St Thomas' Church, Brompton by Northallerton St Thomas' Church on High Green is a Grade I listed building dating from the 12th century with additions in the 14th and 15th centuries and a restoration undertaken in 1868. It is reputed to have the largest collection of Hogback sculptures in the United Kingdom. This collection of hogbacks and Viking period crosses that suggest Brompton was the base for a company of stone carvers during that period. It is thought that the Hogback was invented in the Allertonshire area since the Hogbacks at Brompton and Northallerton are amongst the oldest examples.
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So-called "Saint's tomb" (left), and "Warrior's tomb" (right), two hogbacks in St. Mary's church, Gosforth. Typically high and narrow Cumbrian style, in the shape of a building with a roof, eaves and walls. The Saint's tomb has a crucifixion on the end, the Warrior's tomb has a procession of armed men Cumbria is notable for having the largest number of hogbacks and for their tallness and narrowness compared to other northern stones;Bailey (1980), p. 98. for having a special type of circle-head to the crosses;Bailey (1980), p. 178. for having the most 'hammer-head'- shaped crosses;Bailey (1980), pp. 182-183.
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The Murrieta Hogbacks are underlain by Cretaceous granitic rocks of the Peninsular Ranges Batholith. On the north half of the hogbacks, by foliated biotite-hornblende tonalite and on the southern half by hornblende gabbro. The basalt is potassium-argon dated to 10.4 to 10.8 million years and is a remnant of a channel-filling basalt flow, overlying a thin deposit of unconsolidated gray stream gravel, indicating that the basalt had filled in a former water course.M.P. Kennedy and D.M. Morton, PRELIMINARY GEOLOGIC MAP OF THE U.S. Geological Survey Murrieta 7.5' quadrangle, 1979, RIVERSIDE COUNTY, CALIFORNIA, Version 1.0, USGS, Prepared in cooperation with the CALIFORNIA GEOLOGICAL SURVEY, 2003.
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Resistant beds of sandstone are exposed as hogbacks on the steeply upturned east and west flanks of the anticline and are referred to locally as "reefs." Three perennial rivers (the Muddy, San Rafael, and Price) flow eastward across the San Rafael Swell into the Green and Colorado River systems.
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The erosion of tilted sequences of either stratified sedimentary or igneous rock, homoclines, of alternating resistance to erosion produce distinctive landforms that form a gradational continuum from cuestas through homoclinal ridges to hogbacks. Less resistant beds are preferentially eroded creating valleys that lie between ridges created by the erosion of more resistant beds. For example, the erosion of homoclines consisting of resistant beds of either limestone, sandstone, or both interbedded with weaker, less resistant beds of either shale, siltstone, marl, or combination of them will produce either cuestas, homoclinal ridges, or hogbacks depending on the angle of dip of the strata. The greater the difference in the resistance to erosion, the more pronounced the structural control and relief between valley and ridge crest.
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The formation consists of a basal conglomerate interbedded with shale and siltstone and a sequence of alternating sandstone and shale. The lower conglomerates contain volcanic debris, while the upper beds contain sparse nonvolcanic rock fragments. The shales are reddish brown to purplish while the sandstones are light gray. The sandstones are medium bedded to massive and sometimes form hogbacks.
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The valley consists of various grasses and forbs. The surrounding hogbacks and foothills support a pine-Douglas fir vegetation community.Tate and Gilmore 1999:17 The recovery of floral materials from Bradford House II and other archaeological sites in the valley (Johnson 1997:Table Gl) indicates that local plants such as sunflower, wild plum, acorn, and chokecherry were gathered and used by prehistoric peoples.
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Higham (1986), pp. 308, 310. However, the eventual outcome, in the 880s, was an accommodation with the church community of Cuthbert who were granted lands between the Tees and Forth under Danish overlordship (with a semi-independent lordship based at Bamburgh). 'Giants Grave', St. Andrew's churchyard, Penrith, an unusual arrangement of two Viking-age cross-shafts with four hogbacks (in the foreground).
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The church houses an internationally significant collection of early medieval sculpture known as Govan Stones. All the carved stones come from the churchyard and include interlace-decorated crosses, hogbacks, and burial monuments dating to the 9th - 11th centuries AD. Govan Old and the Govan Stones are open daily between April 1 and October 31 from 1pm-4pm. Admission to the museum is by donation.
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When the homoclinal strata consists of alternating layers of rock that vary hardness and resistance to erosion, their erosion produces either cuestas, homoclinal ridges, or hogbacks depending on the angle of dip of the strata.Thornbury, W. D., 1954, Principles of Geomorphology New York, John Wiley & Sons, 618 pp.Twidale, C.R., and E.M. Campbell (1993) Australian Landforms: Structure, Process and Time. Gleneagles Publishing, Adelaide, South Australia, Australia. 568 pp.
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The South Platte River in Platte Canyon, Colorado, ca. 1978. The Platte Canyon is a deep, narrow, scenic gorge on the South Platte River in the Rocky Mountains of Colorado. The canyon is southwest of Denver on the border between Jefferson and Douglas counties. The canyon is at the entrance to the mountains, where the South Platte emerges through the Rampart Range through the hogbacks onto Eastern Plains.
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In a niche at the east end of the aisle are two carved Viking hogback stones. These are very rare pre-Norman tomb markers that were found under the foundations of a 12th- century wall of the church during restoration in 1896-97. The early 11th century is the latest possible date.C A Parker, The Gosforth District, 1904 The hogbacks are each in the shape of a house.
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The site was used by prehistoric groups during the Middle and Late Archaic periods, as well as the Early Woodland, and Middle Woodland periods. This is a span of 4,500 years.Tucker, Gordon C. Jr., Bradford House II, National Register Inventory—Nomination Form, December 19, 2000, in digital files of National Park Service, Washington, D.C. Bradford House II is located in the Ken-Caryl Valley. The Front Range foothills to the west and the Lyons and Dakota hogbacks to the east frame the valley.
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These landform differ only on the steepness of their backslopes and relative differences in the inclination of their backslopes and frontslopes. These differences depends upon whether the dip of the strata from which they have been eroded are either nearly vertical, moderately dipping, or gently dipping. In general, homoclinal ridges, or strike ridges, are associated with strata that dip between 10° and 30°. The symmetrical ridges that characterize hogbacks develop where the strata dip very steeply at 40° or more.
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Because the slope of a homoclinal ridge dips in the same direction as the sedimentary strata underlying it, the dip angle of this bedding (Ө) can be calculated by v/h= tan(Ө) where v is equal to the vertical distance and h is equal to the horizontal distance perpendicular to the strike of the beds.Easterbrook, DJ (1999) Surface Processes and Landforms, 2nd ed. Prentice-Hall, Inc, Upper Saddle River, New Jersey. Cuestas, homoclinal ridges, and hogbacks comprise a sequence of landforms that form a gradational continuum.
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The Replica Gosforth Cross at Aspatria As vicar at Aspatria, Calverley began to study the ancient relics of that parish. He made intricate drawings of the 'Standing Cross', which at that time stood in its own rectangular socket in the south side of the churchyard, and compared its markings to other artefacts in the county. He also studied the Saxon hogbacks, the swastikas, the two spiral shafts, the spiral fragments and began to draw conclusions, which related to the age and importance of the site of the ancient church. Having realised the importance of these relics he removed them to the vestry.
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Topographic map of the Bighorn Basin (highlighted in orange), formed by the Laramide Orogeny In the United States, these distinctive intermontane basins occur principally in the central Rocky Mountains from Colorado and Utah (Uinta Basin) to Montana and are best developed in Wyoming, with the Bighorn, Powder River, and Wind River being the largest. Topographically, the basin floors resemble the surface of the western Great Plains, except for vistas of surrounding mountains. At most boundaries, Paleozoic through Paleogene units dip steeply into the basins off uplifted blocks cored by Precambrian rocks. The eroded steeply dipping units form hogbacks and flatirons.
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The source of Warm Springs Creek was formerly at an altitude of in Diamond Valley, but is now under Diamond Valley Lake at . The source is now is at an altitude of in Domenigoni Valley, west of Diamond Valley Lake and its West Dam. Warm Springs Creek descends southwest through Domenigoni Valley for , past the site of the former mining settlement of Leon, and runs near the intersection of Leon Road and Scott Road. There, at , it descends into a canyon running south-southwest, passing east of the Murrieta Hogbacks, where an unnamed arroyo that drains French Valley to the northeast joins Warm Springs Creek.
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A fine example of English stonecarving from the period, the Brompton Hogbacks, can be found in Brompton Parish Church. In the Domesday Survey, Norman scribes named the settlement Alvertune, Aluertune and Alretone and there is a reference to the Alvertune wapentac, an area almost identical to the Allertonshire wapentake of the North Riding, which was named after the town. The origin of the town's name is uncertain, though it is believed that the name derives from a derivation of the name Aelfere, Aelfereton translates as the farm belonging to Aelfere or even of King Alfred. Alternatively it may be referring to the Alder trees which grew nearby.
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The result is that we are uncertain not only about when the crosses and hogbacks were made, but also about who caused them to be made. The decline of the monasteries in the later Anglian period probably led to the new Scandinavian, secular lords ordering the stones to be made, but many reflect Anglian (Northumbrian) styles and motifs, and have an amalgamation of Christian concerns (for example, Crucifixion scenes) and Viking iconography and myths (for example, scenes depicting Ragnarök and Wayland the Smith). The classic example of this mingling of pagan and Christian story-telling is the Gosforth Cross.Bailey (1980), ch.6, esp. pp. 126–132.
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Today, thirty monuments are currently on display inside the church, and a single recumbent monument of medieval date remains in the graveyard. Sixteen of the stones that were not brought into the church were thought to have been buried or removed after the demolition of the Harland & Wolff factory building in 1973, but a recent community archaeology dig identified the location of at least three of the lost stones. Work in the near future will assess how many of the ‘lost’ stones survive. Of the thirty-one monuments on display at Govan Old, there is one sarcophagus, two cross-shafts, two upright cross-slabs, five hogbacks, and twenty-one recumbent cross-slabs.
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Many animals, including elk, mule deer, and occasional Big Horn sheep, as well as a variety of carnivores, rabbits, rodents, birds, amphibians, reptiles, and fish are found in the hogbacks and foothills.Tate and Gilmore 1999:Table 2-3; Ludlow 1997 Unworked animal, mostly mammal, bone was found in abundance in the Archaic and Early Ceramic levels (Johnson and Lyons 1997a:49, Table 6). Mule deer dominates the assemblage, followed by elk, bison, and rabbit, with little change in dietary preferences from the earlier to later time periods. Several bone tools (awls, beads, reamers, bone scrapers, and bone drills) and antler flakers were recovered from all cultural levels in the site (Johnson and Lyons 1997a) .
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