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Brown Range
The Brown Range or Sørtindane Peaks () is a group of seven peaks in the Framnes Mountains about south of Mount Twintop in Mac. Robertson Land, Antarctica. Exploration Norwegian cartographers mapped two of the peaks from aerial photographs taken by the Lars Christensen Expedition in 1936, and named them the Sørtindane (South Mountain) Peaks. They are named for D. A. Brown, who was a radio operator at Mawson Station in 1958. Description The Framnes Mountains have elevations up to above sea level, and rise up to above the ice surface. They have dark, weathered charnockite bedrock that is littered with light-colored quartz-rich, granitic gneiss glacial erratics. The Brown Range is about inland. During the late Quaternary the ice sheet thickened by about at the Brown Range. Features Simpson Ridge . An isolated, sharp, serrated ridge situated south of Mount Twintop in the Framnes Mountains, Mac. Robertson Land. Mapped from ANARE surveys, 1954-62. Named by ANCA for C.R. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Board On Geographic Names
The United States Board on Geographic Names (BGN) is a federal body operating under the United States Secretary of the Interior. The purpose of the board is to establish and maintain uniform usage of geographic names throughout the federal government of the United States. History On January 8, 1890, Thomas Corwin Mendenhall, superintendent of the US Coast and Geodetic Survey Office, wrote to 10 noted geographers "to suggest the organization of a Board made up of representatives from the different Government services interested, to which may be referred any disputed question of geographical orthography." President Benjamin Harrison signed executive order 28 on September 4, 1890, establishing the ''Board on Geographical Names''. "To this Board shall be referred all unsettled questions concerning geographic names. The decisions of the Board are to be accepted y federal departmentsas the standard authority for such matters." The board was given authority to resolve all unsettled ques ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Summit
A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. The topography, topographic terms acme, apex, peak (mountain peak), and zenith are synonymous. The term (mountain top) is generally used only for a mountain peak that is located at some distance from the nearest point of higher elevation. For example, a big, massive rock next to the main summit of a mountain is not considered a summit. Summits near a higher peak, with some prominence or isolation, but not reaching a certain cutoff value for the quantities, are often considered ''subsummits'' (or ''subpeaks'') of the higher peak, and are considered part of the same mountain. A pyramidal peak is an exaggerated form produced by ice erosion of a mountain top. Summit may also refer to the highest point along a line, trail, or route. The highest summit in the world is Mount Everest with a height of above sea level. The first official ascent was made by Tenzing Norgay and Sir Edm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Framnes Mountains
The Framnes Mountains are an Antarctic mountain range consisting of Casey Range, Masson Range, David Range, and Brown Range, and adjacent peaks and mountains. The three major ranges and other lesser features were sighted and named in February 1931 by the British Australian New Zealand Antarctic Research Expedition under Douglas Mawson. This coast was also sighted by Norwegian whalers in the same season. The whole area was mapped in detail by Norwegian cartographers from aerial photographs taken by the Lars Christensen Expedition in January 1937. This overall name for the several ranges was given by Lars Christensen after Framnesfjellet, a hill near Sandefjord, Norway. Features of the Framnes Mountains * Brown Range * Butler Nunataks * Casey Range * David Range * Masson Range * Shark Peak * Trilling Peaks * Van Hulssen Nunatak Further reading * Damien Gildea, Mountaineering in Antarctica: complete guide: Travel guide' * James P. Minard, United States. Antarctic Projects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Twintop
Mount Twintop () is a twin-peaked mountain about 6 nautical miles (11 km) south-southwest of Mount Tritoppen in the south part of the David Range, Framnes Mountains. Immediately north of Mount Twintop are the Butler Nunataks, and Venture Dome lies 60 km to the south. Mapped by Norwegian cartographers from air photos taken by the Lars Christensen Expedition (1936–37) and named Tvitoppen (the twin peak). The translated form of the name recommended by Antarctic Names Committee of Australia The Australian Antarctic Names and Medals Committee (AANMC) was established to advise the Government on names for features in the Australian Antarctic Territory and the subantarctic territory of Heard Island and the McDonald Islands. The committee ... (ANCA) has been adopted. See also *List of mountains of East Antarctica Mountains of Mac. Robertson Land {{MacRobertsonLand-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mawson Station
The Mawson Station, commonly called Mawson, is one of three permanent bases and research outposts in Antarctica managed by the Australian Antarctic Division (AAD). Mawson lies in Holme Bay in Mac. Robertson Land, East Antarctica in the Australian Antarctic Territory, a territory claimed by Australia. Established in 1954, Mawson is Australia's oldest Antarctic station and the oldest continuously inhabited Antarctic station south of the Antarctic Circle. Mawson was named in honour of the Australian Antarctic explorer Sir Douglas Mawson. Mawson was listed on the Register of the National Estate in 2001 and listed on the Commonwealth Heritage List on 22 June 2004, reflecting the post-World War Two revival of Australia's scientific research and territorial interests in Antarctica. Purpose Mawson Station is a base for scientific research programs including an underground cosmic ray detector, various long-term meteorological aeronomy and geomagnetic studies, as well as ongoing cons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charnockite
Charnockite () is any orthopyroxene-bearing quartz-feldspar rock formed at high temperature and pressure, commonly found in granulite facies metamorphic regions, ''sensu stricto'' as an endmember of the charnockite series. Charnockite series The ''charnockite suite'' or ''series'' is a particularly widespread form of granofels. Granofels are one of the few non-foliated rocks to form under relatively high temperatures and pressures. This combination is generated only deep in the crust by tectonic forces that operate on a grand scale, so granofels is a product of regional, rather than contact, metamorphism. It is formed mostly from the granite clan of rocks, or occasionally from thoroughly reconstituted clays and shales. It is of wide distribution and great importance in India, Sri Lanka, Madagascar and Africa. It was named by geologist T. H. Holland in 1893 after the tombstone of Job Charnock, in St John's Church in Kolkata, India, which is made of this rock. Composition The c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granitic
A granitoid is a generic term for a diverse category of coarse-grained igneous rocks that consist predominantly of quartz, plagioclase, and alkali feldspar. Granitoids range from plagioclase-rich tonalites to alkali-rich syenites and from quartz-poor monzonites to quartz-rich quartzolites. As only two of the three defining mineral groups (quartz, plagioclase, and alkali feldspar) need to be present for the rock to be called a granitoid, foid-bearing rocks, which predominantly contain feldspars but no quartz, are also granitoids. The terms ''granite'' and ''granitic rock'' are often used interchangeably for granitoids; however, granite is just one particular type of granitoid. Granitoids are diverse; no classification system for granitoids can give a complete and unique characterization of the origin, compositional evolution, and geodynamic environment for the genesis of a granitoid. Accordingly, multiple granitoid classification systems have been developed such as those based ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gneiss
Gneiss ( ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Gneiss forms at higher temperatures and pressures than schist. Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct cleavage. Gneisses are common in the ancient crust of continental shields. Some of the oldest rocks on Earth are gneisses, such as the Acasta Gneiss. Description Orthogneiss from the Czech Republic In traditional English and North American usage, a gneiss is a coarse-grained metamorphic rock showing compositional banding (gneissic banding) but poorly developed schistosity and indistinct cleavage. In other words, it is a metamorphic rock composed of mineral grains easily seen with the unaided eye, which form obvious compositional layers, but which has only a weak tendency to fracture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today, although a third epoch, the Anthropocene, has been proposed but is not yet officially recognised by the ICS). The Quaternary Period is typically defined by the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. Research history In 1759 Giovanni Arduino proposed that the geological strata of northern Italy could be divided into four successive formations or "orders" ( it, quattro ordini). The term "quaternary" was introduced by Jules Desnoye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
