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23-545: Prahl Crags ( 76°4′S 134°43′W  /  76.067°S 134.717°W  / -76.067; -134.717 ) are a group of rock crags at an elevation of 2,750 m on the south slopes of the Mount Moulton massif , in Marie Byrd Land . Mapped by United States Geological Survey (USGS) from ground surveys and U.S. Navy air photos, 1959–66. Named by Advisory Committee on Antarctic Names (US-ACAN) for Sidney R. Prahl ,

46-488: A member of the United States Antarctic Research Program (USARP) team that studied ice sheet dynamics in the area northeast of Byrd Station , 1971–72. [REDACTED]  This article incorporates public domain material from "Prahl Crags" . Geographic Names Information System . United States Geological Survey .   [REDACTED] This Marie Byrd Land location article

69-439: Is a stub . You can help Misplaced Pages by expanding it . Mount Moulton The Prahl Crags are located on the southern slopes of Mount Moulton and are part of a caldera . There, an exposed area of blue ice can be found; this ice contains tephra layers from mainly neighbouring Mount Berlin volcano and some of the ice is almost half a million years old. Mount Moulton lies in Marie Byrd Land of Western Antarctica and in

92-528: Is a range of snow-covered, flat-topped, steep-sided mountains, extending in a north–south direction for 20 nautical miles (37 km; 23 mi) and forming a right angle with the eastern end of the Flood Range in Marie Byrd Land , Antarctica. Download coordinates as: The Ames Range is northwest of the Mount Bursey massif in the Flood Range , from which it is separated by Forrest Pass, and southeast of

115-520: Is no evidence that it was glaciated during its eruptions. Only a few outcrops of Mount Moulton have been dated and these yield ages of 5.3 million years, with further age estimates of 4.9 – 4.7 million years ago, 5.9 million years ago and 1.04 ± 0.04 million years ago at Gawne Nunatak , which is a parasitic cone . There is no evidence of eruptive or thermal activity unlike at its neighbour Mount Berlin. Earthquakes have been recorded at Mount Moulton and are either of volcano-tectonic origin or due to

138-516: Is one of the largest volcanoes in the Flood Range and Ames Range. Only the western part of the Mount Moulton emerges from the ice. Volcanic rocks found at Mount Moulton include pantellerite , phonolite and trachyte ; phenocryst phases found in the pantellerite include aenigmatite , anorthoclase , fayalite , hedenbergite , ilmenite and quartz . A blue ice field has formed within

161-623: The Ames Range . Mount Moulton is an obstacle to ice flow in the West Antarctic Ice Sheet , which has piled up on the mountain and is about 800 metres (2,600 ft) higher on the upstream side. Mount Moulton is formed by a 40-kilometre-long (25 mi) complex of glaciated but largely uneroded shield volcanoes with two or possibly three ice-filled calderas , each of which is about 5–7 kilometres (3.1–4.3 mi) wide. The calderas are 8 kilometres (5.0 mi) apart and located at

184-796: The Berry Glacier and Demas Range . Glaciers draining the range include Coleman Glacier and Rosenberg Glacier on the west side, Jacoby Glacier on the east side and Herbst Glacier to the north. Peaks include Mount Andrus, Mount Boenninghausen, Mount Kosciusco and Mount Kauffman. Other features include Lind Ridge, Gardiner Ridge and Brown Valley. The Ames Range was discovered by the United States Antarctic Service (USAS; 1939–41) and named by Richard E. Byrd for his father-in-law, Joseph Ames. The Ames Range consists of three coalescing shield volcanoes : Mount Andrus, Mount Kosciusko and Mount Kauffman, and Mount Boennighausen. The north slopes of

207-589: The Prahl Crags , Britt Peak and potentially Kohler Dome localities. Additionally the Prahl Crags – remnants of the former caldera rim – are found south, Gawne Nunatak west, Edwards Spur northeast and the Moulton Icefalls on the northern side of the mountain. The total volume of the complex is about 325 cubic kilometres (78 cu mi), comparable to that of Mount Shasta in the Cascade Range , and

230-530: The Antarctic Support Activities group, 1965-67. 75°39′S 132°26′W  /  75.650°S 132.433°W  / -75.650; -132.433 . A ridge extending from Mount Kauffman to Mount Kosciusko in the Ames Range. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for James E. Gardiner, GDI, United States Navy, Construction Driver and member of

253-684: The Army-Navy Trail Party that traversed eastward to establish Byrd Station in 1956. 75°44′S 132°33′W  /  75.733°S 132.550°W  / -75.733; -132.550 . A steep, heavily-crevassed glacier draining the west slopes of the Ames Range between Mount Kosciusko and Mount Boennighausen. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for Theodore J. Rosenberg, ionospheric physicist at Siple Station, 1970-71. 75°48′S 132°06′W  /  75.800°S 132.100°W  / -75.800; -132.100 . A steep glacier draining

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276-659: The Army-Navy Trail Party which blazed trail from Little America V to establish Byrd Station in 1956. 75°38′S 132°12′W  /  75.633°S 132.200°W  / -75.633; -132.200 . A rectangular ice-covered valley between Mount Kauffman and Mount Kosciusko in the northeast end of Ames Range. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN after Thomas I. Brown, USARP meteorologist at Byrd Station in 1963. 75°37′S 132°25′W  /  75.617°S 132.417°W  / -75.617; -132.417 . Prominent mountain 2,365 metres (7,759 ft) high that surmounts

299-607: The Byrd Station Traverse of 1962-63. 75°48′S 132°33′W  /  75.800°S 132.550°W  / -75.800; -132.550 . A ridge forming the south wall of Coleman Glacier. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for Larry W. Lind, glaciologist at Byrd Station, 1968-69. 75°48′S 132°14′W  /  75.800°S 132.233°W  / -75.800; -132.233 . A peak 2 nautical miles (3.7 km; 2.3 mi) southeast of Mount Boennighausen in

322-412: The appearance of the deposits indicates that the eruptions of Mount Berlin were highly explosive. Most likely they eventually fell onto the ice of Mount Moulton, were incorporated in it and then transported downward to the blue ice field. Ames Range The Ames Range ( 75°42′S 132°20′W  /  75.700°S 132.333°W  / -75.700; -132.333  ( Ames Range ) )

345-619: The caldera of Mount Moulton behind the Prahl Crags, and contains ice almost 500,000 years old. It is the oldest dated ice in West Antarctica and much older than ice found elsewhere in West Antarctic ice cores . Such blue ice fields like those found at Mount Moulton form when glaciers run into an obstacle – in this case the Prahl Crags – and part of the ice starts moving vertically as it undergoes ablation processes like sublimation . In

368-882: The case of Mount Moulton, this outcrop of ice is about 600 metres (2,000 ft) long. The ice has been used to reconstruct past climate states in West Antarctica, including the beginning and end of the last interglacial , and shows evidence that the West Antarctic Ice Sheet collapsed during that interglacial. In addition, recognizable tephra layers are found in this ice and appear to originate from explosive eruptions of volcanoes such as Mount Berlin, Mount Takahe and Mount Waesche, although some may come from parasitic vents of Mount Berlin and Mount Moulton. These tephra layers at Mount Moulton crop out in parallel layers and geochemical traits indicate an origin at Mount Berlin although some layers may have been erupted from mafic volcanoes at Mount Moulton and Mount Berlin. Furthermore,

391-533: The drilling program at Byrd Station, 1968-69. He worked at McMurdo Station and other Antarctic areas in several seasons, 1971-76. Features, from south to north, include: 75°53′S 132°34′W  /  75.883°S 132.567°W  / -75.883; -132.567 . A broad ice-filled pass between Mount Bursey, in the Flood Range, and the southern elevations of the Ames Range. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for Robert B. Forrest, USARP glaciologist with

414-594: The east slopes of the Ames Range between Mount Boennighausen and Mount Andrus. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for William J. Jacoby, driller at Byrd Station, 1968-69. 75°40′S 132°07′W  /  75.667°S 132.117°W  / -75.667; -132.117 . The eastern glacier of two that drain the north slopes of Mount Kosciusko and reach Brown Valley. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for Emmett L. Herbst of Holmes and Narver, Inc., who participated in

437-513: The movement of ice along the flanks of the volcano. The mountain is 3,078 metres (10,098 ft) high, rising about 1.7 kilometres (1.1 mi) above the ice surface on its northern flank, and located within the Flood Range ; Mount Berlin lies across the c. 10 kilometres (6.2 mi) wide, high-elevation Wells Saddle 25 kilometres (16 mi) to the west and Kohler Dome is east of Moulton. Even farther east lie Mount Bursey , Mount Andrus , Mount Kosciuszko and Mount Kauffman , in

460-649: The nuclear power plant at McMurdo Station, 1966. He served as Civil Engineer on the staff of the Commander, United States Naval Support Force, Antarctica, 1969-70 and 1970-71. 75°43′S 132°13′W  /  75.717°S 132.217°W  / -75.717; -132.217 . Prominent mountain 2,910 metres (9,550 ft) high that comprises the central portion of the Ames Range. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for Captain Henry M. Kosciusko, United States Navy, Commander of

483-732: The range are in the west of the Usas Escarpment . 75°47′S 132°33′W  /  75.783°S 132.550°W  / -75.783; -132.550 . A steep, heavily-crevassed glacier draining westward from Mount Andrus in the south part of Ames Range. Mapped by the United States Geological Survey (USGS) from surveys and United States Navy air photos, 1959-65. Named by the United States Advisory Committee on Antarctic Names (US-ACAN) for Master Sergeant Clarence N. Coleman, United States Army, member of

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506-705: The region of the West Antarctic Ice Sheet . It is part of a system of volcanoes including Mount Berlin , Mount Takahe and Mount Waesche as well as of recently active subglacial volcanism . The volcano is named for Richard S. Moulton, chief dog driver of the United States Antarctic Service Expedition ; the western end of the Flood Range where Mount Moulton lies was visited by this expedition in December 1940. Other field expeditions took place in 1967–1968, 1977–1978, 1993-1994 and 1999–2000. The volcano appears to be of Pliocene age and there

529-684: The southeast extremity of Ames Range. Mapped by USGS from surveys and United States Navy air photos, 1964-68. Named by US-ACAN for Lieutenant Carl H. Andrus, United States Navy, medical officer and Officer-in-Charge of Byrd Station in 1964. 75°47′S 132°18′W  /  75.783°S 132.300°W  / -75.783; -132.300 . Snow-covered mountain 2,970 metres (9,740 ft) high located 4 nautical miles (7.4 km; 4.6 mi) south-southwest of Mount Kosciusko. Mapped by USGS from surveys and United States Navy air photos, 1959-65. Named by US-ACAN for Lieutenant Commander Thomas L. Boennighausen, CEC, United States Navy, Officer-in-Charge of

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