A mesa 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 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 .
26-782: The Mesa Range ( 73°11′S 162°55′E / 73.183°S 162.917°E / -73.183; 162.917 ( Mesa Range ) ) is a range of flat-topped mesas comprising the Sheehan, Pain, Tobin and Gair Mesas, situated at the head of the Rennick Glacier in Victoria Land , Antarctica. It was given this descriptive name by the northern party of the New Zealand Geological Survey Antarctic Expedition (NZGSAE) of 1962–63. The Gair, Tobin and Pain mesas are in
52-403: 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
78-748: 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
104-564: 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
130-539: 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
156-659: The Detachment A winter party at McMurdo Station, 1967. 73°09′S 163°30′E / 73.150°S 163.500°E / -73.150; 163.500 . A small group of low rock outcrops at the east extremity of Pain Mesa. Named by the southern party of NZGSAE, 1966–67, because the party diverted eastward from their route here to visit Navigator Nunatak . 73°14′S 163°03′E / 73.233°S 163.050°E / -73.233; 163.050 . A pinnacle-type mountain 2,900 metres (9,500 ft) high which forms
182-464: 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
208-539: The Mesa Range, between Pain Mesa on the north and Gair Mesa on the south. Named by the Northern Party of NZGSAE, 1962–63, for James Tobin, surveyor with this party. 73°13′S 162°40′E / 73.217°S 162.667°E / -73.217; 162.667 . A bold rock bluff that forms the northwest end of Tobin Mesa. The bluff exposes an easily accessible section of Jurassic basalt. The feature
234-524: The Northern Party of NZGSAE, 1962–63. 73°08′S 163°00′E / 73.133°S 163.000°E / -73.133; 163.000 . A large mesa just north of Tobin Mesa in the Mesa Range. Named by the northern party of NZGSAE, 1962–63, for Kevin Pain, deputy leader of this party. 72°59′S 162°54′E / 72.983°S 162.900°E / -72.983; 162.900 . A prominent flat-topped summit, 2,605 metres (8,547 ft) high, in
260-545: The east side of Pain Mesa. Named by the northern party of NZGSAE, 1962–63, from its resemblance to the square cap worn by Roman Catholic and some Anglican clerics. 73°06′S 163°12′E / 73.100°S 163.200°E / -73.100; 163.200 . An ice-filled valley indenting the east side of Pain Mesa between Biretta Peak and Diversion Hills. Mapped by USGS from surveys and United States Navy air photos, 1960–64. Named by US-ACAN for Commander Norman J. Mills, United States Navy Reserve, officer in charge of
286-843: The east side of the middle reach of the Rennick Glacier , and the Sheehan Mesa is on the west side. The Monument Nunataks are to the northwest, the Freyberg Mountains to the north, Half-ration Névé and the larger Evans Névé to the northeast, the Southern Cross Mountains to the east, and the Deep Freeze Range to the south. Download coordinates as: 73°01′S 162°18′E / 73.017°S 162.300°E / -73.017; 162.300 . A prominent mesa standing 10 nautical miles (19 km; 12 mi) west-northwest of Pain Mesa in
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#1732791027725312-723: The narrow, northern part of Pain Mesa, situated 11 nautical miles (20 km; 13 mi) east of Silva Ridge. Mapped by the United States Geological Survey (USGS) from surveys and United States Navy air photos, 1960–64. Named by the United States Advisory Committee on Antarctic Names (US-ACAN) for Andrew J. Masley, ionospheric physics scientist at McMurdo Station, summer 1962–63. 73°04′S 163°12′E / 73.067°S 163.200°E / -73.067; 163.200 . A small peak 2,530 metres (8,300 ft) high on
338-493: The north offered the better route from Rennick to Aviator Glacier. 73°32′S 162°43′E / 73.533°S 162.717°E / -73.533; 162.717 . A low hill at the southwest end of Gair Mesa. So named by the northern party of NZGSAE, 1962–63, because the west side of the hill has a noteworthy exposure of light colored sandstone. 73°31′S 162°57′E / 73.517°S 162.950°E / -73.517; 162.950 . A bench-like elevation at
364-472: The northern party of NZGSAE, 1962–63, for Harry Gair, geologist and leader of this party. 73°24′S 162°54′E / 73.400°S 162.900°E / -73.400; 162.900 . A gap between Tobin and Gair Mesas which provides access from upper Rennick Glacier to the Aeronaut Glacier . Named "Veto" by the northern party of NZGSAE, 1962–63, because it decided that Pinnacle Gap to
390-415: The northwest part of Mesa Range. Named by the northern party of NZGSAE, 1962–63, for Maurice Sheehan, field assistant with this party. 72°59′S 162°17′E / 72.983°S 162.283°E / -72.983; 162.283 . A ridge leading to the top of Sheehan Mesa, on the northeast side. Large silicified tree stumps in place of growth were found halfway up this ridge, hence named Silva by
416-699: 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
442-422: 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,
468-421: The south end of Pain Mesa and the north side of the entrance to Pinnacle Gap. Mapped by USGS from surveys and United States Navy air photos, 1960–64. Named by US-ACAN for Commander Justin G. Ballou, United States Navy, officer in charge of the Detachment A winter party at McMurdo Station, 1966. 73°17′S 162°52′E / 73.283°S 162.867°E / -73.283; 162.867 . A large mesa in
494-460: The southeast end of Gair Mesa that overlooks the head of Campbell Glacier . Named by the northern party of NZGSAE, 1962–63, because of a dog fight here in which one dog was so badly torn that its wounds required sutures. [REDACTED] This article incorporates public domain material from websites or documents of the United States Geological Survey . Mesa As noted by geologist Kirk Bryan in 1922, mesas "...stand distinctly above
520-436: The southeast side of Pinnacle Gap. So named by the northern party of NZGSAE, 1962–63, because the feature provides a good "watchtower" to the entrance of Pinnacle Gap. 73°18′S 163°00′E / 73.300°S 163.000°E / -73.300; 163.000 . A bold rock spur 3 nautical miles (5.6 km; 3.5 mi) north of Scarab Peak, extending northeast from the east central part of Tobin Mesa. The feature
546-690: The southeast end of Tobin Mesa. Named by the northern party of the NZGSAE, 1962–63, for its resemblance to a scarab beetle. 73°23′S 162°55′E / 73.383°S 162.917°E / -73.383; 162.917 . A large pyramidal shaped table mountain, 3,100 metres (10,200 ft) high, standing between Mount Fazio and Scarab Peak in the south part of Tobin Mesa. Named by the northern party of NZGSAE, 1962–63, for its frustum -like shape. 73°23′S 162°48′E / 73.383°S 162.800°E / -73.383; 162.800 . An ice-free mountain, 2,670 metres (8,760 ft) high, marking
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#1732791027725572-399: The southwest end of Tobin Mesa. Mapped by USGS from surveys and United States Navy air photos, 1960–64. Named by US-ACAN for William Z. Fazio, United States Navy, helicopter crewmember during United States Navy OpDFrz, 1966, 1967 and 1968. 73°28′S 162°52′E / 73.467°S 162.867°E / -73.467; 162.867 . The southernmost mesa of the Mesa Range. Named by
598-417: 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,
624-474: 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
650-403: Was geologically studied by an Ohio State University field party during the 1982–83 season. Named by US-ACAN after Marta A. Haban, a geologist in the party. 73°21′S 163°01′E / 73.350°S 163.017°E / -73.350; 163.017 . A prominent peak, 3,160 metres (10,370 ft) high, located 2 nautical miles (3.7 km; 2.3 mi) northeast of Mount Frustum in
676-570: Was studied by Ohio State University geological parties in 1981–82 and 1982–83. Named by US-ACAN after Mary A. Siders, geologist in those field parties. A gap between Pain and Tobin Mesas. The feature was traversed and so named by the northern party of NZGSAE, 1962-63, because it is readily identified by the high rock pinnacle (Mount Ballou) on the north ridge overlooking the gap. 73°16′S 163°08′E / 73.267°S 163.133°E / -73.267; 163.133 . A small, pointed hill at
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