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21-565: Cedar Mesa is a tableland in San Juan County in the southeastern portion of the U.S. state of Utah . It extends from Elk Ridge in the north, Comb Wash to the east, the gorge of the San Juan River to the south, and Grand Gulch to the west, an area of over 400 square miles (1,000 km). The center of the mesa is located at approximately 37°26'N and 109°55'W, at an elevation of 6,500 feet (2,000 m). The surrounding terrain has

42-409: A dip slope that conforms with the dip of resistant strata , called caprock . Where erosion has exposed the frontslope of this, a steep slope or escarpment occurs. The resulting terrain may be called scarpland . In general usage, a cuesta is a hill or ridge with a gentle slope (backslope) on one side, and a steep slope (frontslope) on the other. The word is from Spanish : "flank or slope of

63-411: A hill; hill, mount, sloping ground". In geology and geomorphology, cuesta refers specifically to an asymmetric ridge with a long and gentle backslope called a dip slope that conforms with the dip of a resistant stratum or strata, called caprock. The outcrop of the caprock forms a steeper or even cliff-like frontslope (escarpment), cutting through the dipping strata that comprise the cuesta. Cuestas are

84-483: A typical elevation of just 4,200 feet (1,300 m) Most of Cedar Mesa is included in the newly declared (2016) Bears Ears National Monument . This large difference in elevation has led to the formation of numerous canyons, cliffs, and other erosional features on the edges of the mesa. To the east are several canyons draining into Comb Wash, including Arch , Texas, Mule , Owl , Fish , McCloyd, and Road Canyons. Scattered throughout these canyons are cliff dwellings of

105-426: Is a stub . You can help Misplaced Pages by expanding it . Cuesta A cuesta ( Spanish for 'slope') is a hill or ridge with a gentle slope on one side, and a steep slope on the other. In geology, the term is more specifically applied to a ridge where a harder sedimentary rock overlies a softer layer, the whole being tilted somewhat from the horizontal. This results in a long and gentle backslope called

126-422: Is equal to the vertical distance and h is equal to the horizontal distance perpendicular to the strike of the beds. Cuestas, homoclinal ridges , and hogbacks comprise a sequence of landforms that form a gradational continuum. These landforms differ only on the steepness of their backslopes and the relative differences in the inclination of their backslopes and frontslopes. These differences depend upon whether

147-680: The Ancient Puebloans . To the southeast is an eroded area called the Valley of the Gods , and to the southwest is a deep gorge of the San Juan River, called the Goosenecks . High above, on the southern edge of Cedar Mesa, are Muley and Cedar Points. The west side of Cedar Mesa also includes large canyons, including John's and Slickhorn Canyons, and the combination of Grand Gulch and Bullet Canyon known as

168-670: The Grand Gulch Primitive Area . To the northwest is the Natural Bridges National Monument and Stimper Arch . State Route 95 crosses the northern part of Cedar Mesa, while U.S. Route 163 passes to the south. Running up the center of the mesa is State Route 261 . Gravel and dirt roads provide access in dry weather to the individual canyons, through the Valley of the Gods, and to Comb Wash. As early as 13,000 years ago Clovis people , who are considered to be

189-667: The Onondaga escarpment and the Niagara Escarpment . The dip of the Onondaga is about 40 feet per mile (about 7.6 m/km) to the south. In their most populated sections both escarpments edges face north, running roughly parallel to the southern Lake Ontario shoreline and, for the former, the Mohawk River. The Gulf Coastal Plain in Texas is punctuated by a series of cuestas that parallel

210-722: The ancestors of most of the indigenous cultures of the Americas , hunted in Cedar Mesa using " Clovis points ". One of the oldest known archaeological sites with Clovis tools in Utah is Lime Ridge Clovis Site. Tableland A tableland is an area containing elevated landforms characterized by a distinct, flat, nearly level, or gently undulating surface. They often exhibit steep, cliff-like edges, known as escarpments , that separate them from surrounding lowlands. Depending on either their size, other physical characteristics, or geographic location,

231-668: The coast, as are most coastal plains. The Reynosa Plateau is the most coast-ward cuesta, which has surface expression with the Bordes-Oakville escarpment, on the northwest side and a low ridge on the eastern boundary, called the Reynosa Cuesta, where the deposits dip below later Pliocene - Pleistocene deposits of the Willis and Lissie Formations. Cuestas have less dramatic expression in the United Kingdom, with two notable examples being

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252-594: The dip of the strata from which they have been eroded are either nearly vertical, moderately dipping, or gently dipping. Because of their gradational nature, the exact angle of the backslope that separates these landforms is arbitrary and some differences in the specific angles used to define these landforms occur in the scientific literature. It also can be difficult to sharply distinguish immediately adjacent members of this series of landforms because of their gradational nature. In North America , two well-known cuestas in western/central New York and southern Ontario are

273-459: The erosion of duricrusts are also quite common in parts of Australia and South America. In addition, the eruption of either lava or pyroclastic flows can deposit a solid surface layer of volcanic rock that is relatively flat. As in case of the duricrusts, the resulting lava or pyroclastic flows are sufficiently tough to form the flat-lying caprock of tablelands when breached and incised by rivers and streams. This article related to topography

294-425: The expression of extensive outcrops of gently dipping strata, typically sedimentary strata, that consist of alternating beds of weak or loosely cemented strata, i.e. shale , mudstone , and marl and hard, well-lithified strata, i.e. sandstone and limestone . The surfaces of the hard, erosion-resistant rock strata form the caprock of the backslope (dip-slope) of the cuesta, where erosion has preferentially removed

315-595: The form of relatively flat-lying sandstones and conglomerates that have not been strongly deformed by tectonics . The primary control on the geomorphology of sedimentary tablelands is the dip of the layers of the sandstones, conglomerates, and associated sedimentary strata . Sedimentary tablelands only form if the dip of the sedimentary layers is negligible. If the sedimentary layers are tilted, although otherwise little deformed, asymmetric ridges known as cuestas develop. A really extensive sedimentary tablelands are often known as plateaus . As plateaus are dissected by

336-412: The formation of a thick indurated surface layer duricrust by deep weathering beneath a relatively flat surface. Second, the breaching and incision of the duricrust layer by rivers or streams. Finally, the inward migration of valley walls and escarpments by slope erosion and denudation of mesas and buttes. An example of such tablelands is the laterite-capped Panchgani Tableland of India. Tablelands formed by

357-499: The headward erosion and incision of river and stream courses and the retreat of their bounding escarpments, plateaus are fragmented into tablelands of smaller and smaller extent known as mesas , buttes , or pinnacles . Further erosion eventually reduces these landforms to piles of bouderly rubble as known as rock labyrinths . The tepui of South America are a type of sedimentary tableland composed of erosional outliers of flat-lying Precambrian quartz arenite sandstone that tower over

378-440: The landforms comprising a tableland are individually referred to by a number of names including either butte , mesa , plateau , potrero , tepui , or tuya . Table Mountains are also a type of tableland. A homologous landform under the sea is called either a tablemount or guyot . Sedimentary tablelands are tablelands that typically have developed from the erosion of coarse-grained, clastic, sedimentary rocks in

399-937: The northwest-facing escarpment of the Cretaceous chalk White Horse Hills and the similarly aligned escarpment of the Jurassic limestones in the Cotswolds , sometimes called the Cotswold Edge. Other examples include the Brecon Beacons, Wenlock Edge, the Chilterns, the North and South Downs and the Greensand Ridge of Kent and Surrey In continental Europe, the Swabian Alb offers particularly good views of cuestas in Jurassic rock. In France ,

420-426: The surrounding jungle underlain by crystalline basement rocks. Flat-lying, coarse-grained, clastic sedimentary rocks are not the only layered rocks that serve as the caprock that form the surface of tablelands. Flat-lying duricrusts and volcanic rocks also form the caprock of various tablelands. In case of duricrusts, e.g. laterite or silcrete , the formation of tablelands involves a three stage process. First,

441-479: The weaker strata. The frontslope of the cuesta consists of an escarpment that cuts across the bedding of the strata comprising it. Because of the gently dipping nature of the strata that forms a cuesta, a significant shift in horizontal location will take place as the landscape is lowered by erosion . Because the slope of a cuesta dips in the same direction as the sedimentary strata, the dip angle of this bedding (θ) can be calculated by ( v / h ) = tan(θ) where v

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