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Baker Rocks
The Random Hills () are a group of rugged hills in Victoria Land, Antarctica. Bounded on the west by Campbell Glacier and on the east by Tinker Glacier and Wood Bay, centered about 15 nautical miles (28 km) north-northwest of Mount Melbourne, they were named by the Southern Party of the New Zealand Geological Survey Antarctic Expedition (NZGSAE), 1966–67, because of the random orientation of the ridges which comprise the feature. The Random Hills are part of the Melbourne Volcanic Province of the McMurdo Volcanic Group. K–Ar or Rb–Sr dating has given ages of 12.63 ± 0.17 million years and 12.43 ± 0.16 million years for Random Hills hawaiite. Features * Clausnitzer Glacier * Mount McGee * Harrow Peaks The Random Hills () are a group of rugged hills in Victoria Land, Antarctica. Bounded on the west by Campbell Glacier and on the east by Tinker Glacier and Wood Bay, centered about 15 nautical miles (28 km) north-northwest of Mount Melbourne, ... References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hill
A hill is a landform that extends above the surrounding terrain. It often has a distinct Summit (topography), summit. Terminology The distinction between a hill and a mountain is unclear and largely subjective, but a hill is universally considered to be not as tall, or as Grade (slope), steep as a mountain. Geographers historically regarded mountains as hills greater than above sea level, which formed the basis of the plot of the 1995 film ''The Englishman who Went up a Hill but Came down a Mountain''. In contrast, hillwalkers have tended to regard mountains as peaks above sea level. The ''Oxford English Dictionary'' also suggests a limit of and Whittow states "Some authorities regard eminences above as mountains, those below being referred to as hills." Today, a mountain is usually defined in the UK and Ireland as any summit at least high, while the official UK government's definition of a mountain is a summit of or higher. Some definitions include a topographical pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K–Ar Dating
Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar). Potassium is a common element found in many materials, such as feldspars, micas, clay minerals, tephra, and evaporites. In these materials, the decay product is able to escape the liquid (molten) rock, but starts to accumulate when the rock solidifies ( recrystallizes). The amount of argon sublimation that occurs is a function of the purity of the sample, the composition of the mother material, and a number of other factors. These factors introduce error limits on the upper and lower bounds of dating, so that the final determination of age is reliant on the environmental factors during formation, melting, and exposure to decreased pressure or open air. Time since recrystallization is calculated by measuring the ratio of the amount of accumulated to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borchgrevink Coast
The Borchgrevink Coast is that portion of the coast of Victoria Land between Cape Adare and Cape Washington. The name was recommended by New Zealand Antarctic Place-Names Committee in 1961 after Carsten Borchgrevink, a member of Henrik Johan Bull's expedition to this area, 1894–95, and leader of the British Antarctic Expedition, 1898–1900, the first to winter on the continent, at Cape Adare. Landmarks *Agate Peak is a peak situated in the southeast area of the Intention Nunataks, at the southwest margin of Evans Neve within the Borchgrevink Coast. So named by the New Zealand Antarctic Place-Names Committee because agate and other semi-precious stones were found here by the Southern Party of New Zealand Geological Survey Antarctic Expedition, 1966–67. See also *Borchgrevink Canyon Borchgrevink Canyon () is an undersea canyon on the continental rise east of Iselin Bank in the Ross Sea. It was named in association with Borchgrevink Coast The Borchgrevink Coast is that portio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hills Of Victoria Land
A hill is a landform that extends above the surrounding terrain. It often has a distinct summit. Terminology The distinction between a hill and a mountain is unclear and largely subjective, but a hill is universally considered to be not as tall, or as steep as a mountain. Geographers historically regarded mountains as hills greater than above sea level, which formed the basis of the plot of the 1995 film '' The Englishman who Went up a Hill but Came down a Mountain''. In contrast, hillwalkers have tended to regard mountains as peaks above sea level. The ''Oxford English Dictionary'' also suggests a limit of and Whittow states "Some authorities regard eminences above as mountains, those below being referred to as hills." Today, a mountain is usually defined in the UK and Ireland as any summit at least high, while the official UK government's definition of a mountain is a summit of or higher. Some definitions include a topographical prominence requirement, typically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harrow Peaks
The Random Hills () are a group of rugged hills in Victoria Land, Antarctica. Bounded on the west by Campbell Glacier and on the east by Tinker Glacier and Wood Bay, centered about 15 nautical miles (28 km) north-northwest of Mount Melbourne, they were named by the Southern Party of the New Zealand Geological Survey Antarctic Expedition (NZGSAE), 1966–67, because of the random orientation of the ridges which comprise the feature. The Random Hills are part of the Melbourne Volcanic Province of the McMurdo Volcanic Group. K–Ar or Rb–Sr dating has given ages of 12.63 ± 0.17 million years and 12.43 ± 0.16 million years for Random Hills hawaiite Hawaiite is an olivine basalt with a composition between alkali basalt and mugearite. It was first used as a name for some lavas found on the island of Hawaii. It occurs during the later stages of volcanic activity on oceanic islands such as Haw .... Features * Clausnitzer Glacier * Mount McGee * Harrow Peaks Referenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount McGee
The Random Hills () are a group of rugged hills in Victoria Land, Antarctica. Bounded on the west by Campbell Glacier and on the east by Tinker Glacier and Wood Bay, centered about 15 nautical miles (28 km) north-northwest of Mount Melbourne, they were named by the Southern Party of the New Zealand Geological Survey Antarctic Expedition (NZGSAE), 1966–67, because of the random orientation of the ridges which comprise the feature. The Random Hills are part of the Melbourne Volcanic Province of the McMurdo Volcanic Group. K–Ar or Rb–Sr dating has given ages of 12.63 ± 0.17 million years and 12.43 ± 0.16 million years for Random Hills hawaiite. Features * Clausnitzer Glacier * Mount McGee * Harrow Peaks The Random Hills () are a group of rugged hills in Victoria Land, Antarctica. Bounded on the west by Campbell Glacier and on the east by Tinker Glacier and Wood Bay, centered about 15 nautical miles (28 km) north-northwest of Mount Melbourne, ... Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clausnitzer Glacier
The Tinker Glacier is a 40 kilometre (25 mile) long glacier in Antarctica, draining the central part of the Southern Cross Mountains and flowing SE into Wood Bay, on the coast of Victoria Land. Named by the Northern Party of the New Zealand Geological Survey Antarctic Expedition (NZGSAE), 1962–63, for Lieutenant Col. Ron Tinker, leader at Scott Base during that season. The Tinker Glacier Tongue is the seaward extension of the Tinker Glacier, projecting into the NW corner of Wood Bay on the coast of Victoria Land. The name was suggested by Advisory Committee on Antarctic Names The Advisory Committee on Antarctic Names (ACAN or US-ACAN) is an advisory committee of the United States Board on Geographic Names responsible for recommending commemorative names for features in Antarctica. History The committee was established ... (US-ACAN). References Glaciers of Victoria Land Borchgrevink Coast {{BorchgrevinkCoast-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Society Of America
The Geological Society of America (GSA) is a nonprofit organization dedicated to the advancement of the geosciences. History The society was founded in Ithaca, New York, in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitchcock, John R. Procter and Edward Orton and has been headquartered at 3300 Penrose Place, Boulder, Colorado, US, since 1967. GSA began with 100 members under its first president, James Hall. In 1889 Mary Emilie Holmes became its first female member. It grew slowly but steadily to 600 members until 1931, when a nearly $4 million endowment from 1930 president R. A. F. Penrose Jr. jumpstarted GSA's growth. As of December 2017, GSA had more than 25,000 members in over 100 countries. The society has six regional sections in North America, three interdisciplinary interest groups, and eighteen specialty divisions. Activities The stated mission of GSA is "to advance geoscience research and discovery, service to society, stewardship of Earth, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaiite
Hawaiite is an olivine basalt with a composition between alkali basalt and mugearite. It was first used as a name for some lavas found on the island of Hawaii. It occurs during the later stages of volcanic activity on oceanic islands such as Hawaii, which happens to be when the alkaline metals are most present. In gemology, hawaiite is a colloquial term for Hawaii-originated peridot, which is a gem-quality form of the mineral olivine. Description Hawaiite is an aphanitic (fine-grained) volcanic rock produced by rapid cooling of lava moderately poor in silica and enriched in alkali metal oxides (potassium oxide plus sodium oxide). It is often impractical to determine the mineral composition of such a fine-grained rock, and so hawaiite is defined chemically. Under the TAS classification, hawaiite is sodic trachybasalt, with a silica content close to 49 wt%, a total alkali metal oxide content close to 6%, and wt% > wt% + 2. This places hawaiite in the S1 field of the TAS dia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium–strontium Dating
The rubidium-strontium dating method is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87Rb) and strontium (87Sr, 86Sr). One of the two naturally occurring isotopes of rubidium, 87Rb, decays to 87Sr with a half-life of 49.23 billion years. The radiogenic daughter, 87Sr, produced in this decay process is the only one of the four naturally occurring strontium isotopes that was not produced exclusively by stellar nucleosynthesis predating the formation of the Solar System. Over time, decay of 87Rb increases the amount of radiogenic 87Sr while the amount of other Sr isotopes remains unchanged. The ratio 87Sr/86Sr in a mineral sample can be accurately measured using a mass spectrometer. If the amount of Sr and Rb isotopes in the sample when it formed can be determined, the age can be calculated from the increase in 87Sr/86Sr. Different minerals that crystallized from the same silicic melt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
McMurdo Volcanic Group
The McMurdo Volcanic Group is a large group of Cenozoic volcanic rocks in the western Ross Sea and central Transantarctic Mountains areas of Antarctica. It is one of the largest provinces of alkaline volcanism in the world, having formed as a result of continental rifting along the West Antarctic Rift System. The McMurdo Volcanic Group is part of the Western Ross Supergroup, a stratigraphic unit that also includes the Meander Intrusive Group. Subdivisions Three subprovinces comprise the McMurdo Volcanic Group, namely the Hallett, Melbourne and Erebus volcanic provinces. The Balleny Volcanic Province along the Balleny Fracture Zone in the Southern Ocean was originally defined as part of the McMurdo Volcanic Group but is now excluded due to its location on oceanic crust with no obvious geographic or tectonic relationship to the other McMurdo volcanic provinces. Hallett Volcanic Province The Hallett Volcanic Province in northern Victoria Land is situated along the margin of the Tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victoria Land
Victoria Land is a region in eastern Antarctica which fronts the western side of the Ross Sea and the Ross Ice Shelf, extending southward from about 70°30'S to 78°00'S, and westward from the Ross Sea to the edge of the Antarctic Plateau. It was discovered by Captain James Clark Ross in January 1841 and named after Queen Victoria. The rocky promontory of Minna Bluff is often regarded as the southernmost point of Victoria Land, and separates the Scott Coast to the north from the Hillary Coast of the Ross Dependency to the south. The region includes ranges of the Transantarctic Mountains and the McMurdo Dry Valleys (the highest point being Mount Abbott in the Northern Foothills), and the flatlands known as the Labyrinth. The Mount Melbourne is an active volcano in Victoria Land. Early explorers of Victoria Land include James Clark Ross and Douglas Mawson. In 1979, scientists discovered a group of 309 meteorites in Antarctica, some of which were found near the Allan Hills in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
