Ruthven Bluff (82°34′S 42°54′W / 82.567°S 42.900°W / -82.567; -42.900) is a large rock bluff 1 nautical mile (1.9 km) south of Sosa Bluff in the Schneider Hills portion of the Argentina Range, Pensacola Mountains. Mapped by United States Geological Survey (USGS) from surveys and U.S. Navy air photos, 1956–67. Named by Advisory Committee on Antarctic Names (US-ACAN) for Richard W. Ruthven, USGS surveyor who visited the bluff in the 1965–66 season.[1]

Geology edit

Ruthven Bluff is an approximately 250 meters (820 ft) high bluff of Cambrian limestone. This bluff exposes a thick archaeocyathid reef composed of massive boundstone. At this locality, the boundstone contains numerous irregular cavities that are 50 to 100 mm (2.0 to 3.9 in) in diameter. These cavities are lined with fibrous cement and filled with either ferroancalcite or internal sediment. At Ruthven Bluff, alternating beds of grainstone and burrowed packstone encase this reef. The packstone beds contain subparallel zones of calcite-filled burrows up to 0.5 meters (1.6 ft) thick.[2][3]

References edit

  1. ^ "Ruthven Bluff". Geographic Names Information System. United States Geological Survey, United States Department of the Interior. Retrieved 2011-11-16.
  2. ^ Rowell, A.J., Rees, M.N. and Evans, K.R., 1992. Depositional setting of the Lower and Middle Cambrian in the Pensacola Mountains. Antarctic Journal of the United States, 25, pp. 40-42.
  3. ^ Stilwell, J.D., and Long, J.A., 2011. Frozen in time: prehistoric life in Antarctica. Collingwood, Victoria, Australia, CSIRO Publishing. 238 pp. ISBN 978-0-6430-9635-6