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21-578: The Pink Cliffs are a series of highly dissected cliffs on the Colorado Plateau in Garfield , Iron , and Kane counties in southwestern Utah , United States . Contrary to the implication of the name, the cliffs are not a single set of rock formations, but actually a geological formation that manifests itself in multiple sets of rock formations. The cliffs form a large number of unique rock formations, many of which are protected by either

42-490: A mesa. The caprock can consist of either sedimentary rocks such as sandstone and limestone ; dissected lava flows ; or a deeply eroded duricrust . Unlike plateau , whose usage does not imply horizontal layers of bedrock , e.g. Tibetan Plateau , the term mesa applies exclusively to the landforms built of flat-lying strata . Instead, flat-topped plateaus are specifically known as tablelands . As noted by geologist Kirk Bryan in 1922, mesas "...stand distinctly above

63-403: A section can be cut off from the main cliff, forming a mesa. Basal sapping occurs as water flowing around the rock layers of the mesa erodes the underlying soft shale layers, either as surface runoff from the mesa top or from groundwater moving through permeable overlying layers, which leads to slumping and flowage of the shale. As the underlying shale erodes away, it can no longer support

84-748: A steep cliff or slope and representing an erosion remnant also have been called mesas. In the English-language geomorphic and geologic literature, other terms for mesa have also been used. For example, in the Roraima region of Venezuela, the traditional name, tepui , from the local Pomón language, and the term table mountains have been used to describe local flat-topped mountains. Similar landforms in Australia are known as tablehills , table-top hills, tent hills, or jump ups ( jump-ups). The German term Tafelberg has also been used in

105-414: Is a plateau area that has been severely eroded such that the relief is sharp. Such an area may be referred to as mountainous, but dissected plateaus are distinguishable from orogenic mountain belts by the lack of folding , metamorphism , extensive faulting , or magmatic activity that accompanies orogeny . A dissected plateau may also be formed, or created, usually on a comparatively small scale, by

126-406: Is an isolated, flat-topped elevation , ridge or hill , which is bounded from all sides by steep escarpments and stands distinctly above a surrounding plain . Mesas characteristically consist of flat-lying soft sedimentary rocks capped by a more resistant layer or layers of harder rock , e.g. shales overlain by sandstones . The resistant layer acts as a caprock that forms the flat summit of

147-564: Is called differential erosion. The most resistant rock types include sandstone , conglomerate , quartzite , basalt , chert , limestone , lava flows and sills . Lava flows and sills, in particular, are very resistant to weathering and erosion, and often form the flat top, or caprock , of a mesa. The less resistant rock layers are mainly made up of shale , a softer rock that weathers and erodes more easily. The differences in strength of various rock layers are what give mesas their distinctive shape. Less resistant rocks are eroded away on

168-795: Is still widely known in Britain by the older name of boulder clay. Dissected volcanic plateaus include the Pajarito Plateau in New Mexico , on the skirt of the enormous Valles Caldera . Isolated portions of this plateau are known as mesas , and long, connected portions are known as potreros . The Allegheny Plateau , the Cumberland Plateau , the Ozark Plateau , and the Catskill Mountains in

189-939: The Bryce Canyon National Park or the Cedar Breaks National Monument . Most of the other formations are located within the Dixie National Forest . Geologically the cliffs are pink- and red-colored Claron Formation limestones , forming the upper riser of the Grand Staircase (which descends southward to the Grand Canyon in Arizona ). The Pink Cliffs, as well as the other layers of the Grand Staircase, were named by geologist Clarence Dutton in

210-776: The Markagunt Plateau (mostly within Cedar Breaks National Monument) in southeastern Iron County and the easternmost part of the cliffs are located on the southeastern edge of the Paunsaugunt Plateau in southwestern Garfield County (mostly within Bryce Canyon National Park). From the national monument on the west, the cliffs wrap south around the southern edge of the Markagunt Plateau (roughly along

231-547: The 1870s. While it is not an uncommon belief that the extent of the Pink Cliff is limited to the Bryce Canyon National Park area (being one of the best and most popular areas to view the cliffs), geographically , the cliffs actually extend well beyond the national park, forming a rough, but wide, "U" shape that spans three counties. The westernmost part of the cliffs are located on the western edge of

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252-539: The Cockburn Range of North Western Australia have areas as large as 350 km (140 sq mi). In contrast, flat topped hills with areas as small as 0.1 km (0.039 sq mi) in the Elbe Sandstone Mountains , Germany , are described as mesas. Less strictly, a very broad, flat-topped, usually isolated hill or mountain of moderate height bounded on at least one side by

273-464: The English scientific literature in the past. Mesas form by weathering and erosion of horizontally layered rocks that have been uplifted by tectonic activity. Variations in the ability of different types of rock to resist weathering and erosion cause the weaker types of rocks to be eroded away, leaving the more resistant types of rocks topographically higher than their surroundings. This process

294-832: The United States, the Blue Mountains and Hornsby Plateau in Australia and the Deccan Plateau in India are examples of dissected plateaus formed after regional uplift. These older uplifts have been eroded by creeks and rivers to develop steep relief not immediately distinguishable from mountains . Many areas of the Allegheny Plateau and the Cumberland Plateau, which are at

315-580: The border of the Dixie National Forest ) and run just south of Navajo Lake in northeastern Kane County. After being bisected by the Long Valley and the valley of Kanab Creek , the cliffs wrap around the southern and southeastern edges of the Paunsaugunt Plateau and extend north through and just beyond the national park. [REDACTED] Media related to Pink Cliffs at Wikimedia Commons Dissected plateau A dissected plateau

336-406: The levelling of terrain by planing and deposition beneath an ice sheet or perhaps, an ice cap . Subsequently, during the same or a later glacial , the margins of the glacial till plain are removed by glaciers , leaving the plateau into which erosion by water incises valleys . Such a plateau may be level or gently sloping but may be distinguished by the till caps on its hills. Glacial till

357-699: The overlying cliff layers, which collapse and retreat. When the caprock has caved away to the point where only little remains, it is known as a butte . Many but not all American mesas lie within the Basin and Range Province . A transitional zone on Mars , known as fretted terrain , lies between highly cratered highlands and less cratered lowlands. The younger lowland exhibits steep walled mesas and knobs . The mesa and knobs are separated by flat lying lowlands. They are thought to form from ice-facilitated mass wasting processes from ground or atmospheric sources. The mesas and knobs decrease in size with increasing distance from

378-422: The sides are broken into a staircase pattern called "cliff-and-bench topography". The more resistant layers form the cliffs, or stairsteps, while the less resistant layers form gentle slopes, or benches, between the cliffs. Cliffs retreat and are eventually cut off from the main cliff, or plateau , by basal sapping. When the cliff edge does not retreat uniformly but instead is indented by headward eroding streams,

399-417: The surface into valleys, where they collect water drainage from the surrounding area, while the more resistant layers are left standing out. A large area of very resistant rock, such as a sill, may shield the layers below it from erosion while the softer rock surrounding it is eroded into valleys, thus forming a caprock. Differences in rock type also reflect on the sides of a mesa, as instead of smooth slopes,

420-474: The surrounding country, as a table stands above the floor upon which it rests". It is from this appearance that the term mesa was adopted from the Spanish word mesa , meaning "table". A mesa is similar to, but has a more extensive summit area than a butte . There is no agreed size limit that separates mesas from either buttes or plateaus. For example, the flat-topped mountains which are known as mesas in

441-476: The western edge of the Appalachian Mountains of eastern North America , are called "mountains" but are actually dissected plateaus. One can stand on the top of one of these high "mountains" and note that all the other tops are nearly the same height, which represents the original elevation profile of the plain before uplift, and thereafter the subsequent weather erosion. Mesa A mesa

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