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Mount Joyce
Mount Joyce is a prominent, dome-shaped mountain, high, standing on the south side of David Glacier, northwest of Mount Howard in the Prince Albert Mountains of Victoria Land, Antarctica. It was first mapped by the British Antarctic Expedition, 1907–09, which named it for Ernest Joyce who was in charge of general stores, dogs, sledges, and zoological collections with the expedition and who had earlier been with the British National Antarctic Expedition, 1901–04. Joyce was also with the Ross Sea party of Shackleton's Imperial Trans-Antarctic Expedition, 1914–17. Geology Mount Joyce, along with nearby nunataks, such as the Trio Nunataks, represents the remnants of a tableland of the Jurassic Ferrar Group, which consists of Kirkpatrick lavas and Ferrar dolerite sills, alternating with rafts of sandstone of the Paleozoic and Mesozoic Beacon Supergroup. The strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by cer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Glacier
David Glacier is the most imposing outlet glacier in Victoria Land, Antarctica. It is named after the geologist Edgeworth David and is fed by two main flows which drain an area larger than 200,000 square kilometres of the East Antarctic plateau, with an estimated ice discharge rate of 7.8 +/- 0.7 km³/year.Frezzotti,M., A.Capra and L.Vittuari, Ann.Glaciol, v27, 54-60 (1998) The northern flow drains from Talos Dome to the Ross Sea, but the main branch of the stream is fed by a network of tributaries which drain a common area of the inner plateau around Dome C and converge in a spectacular icefall normally known as the David Cauldron.Danesi et al., Earth and Planetary Science Letters, v253, p151-158 (2007) The north wall of David Glacier, near its terminus at Cape Philippi, is named D'Urville Wall after Admiral Jules Dumont d'Urville. As the David Glacier flows into the Ross Sea, it forms a floating mass known as the Drygalski Ice Tongue. Hughes Bluff lies nearby. See al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic, Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province. The beginning of the Toarcian Stage started around 183 million years ago and is marked by an extinction event associated with widespread Anoxic event, oceanic anoxia, ocean acidification, and elevated temperatures likely caused by the eruption of the Karoo-Ferrar, Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear boundary with the Cretaceous and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum
In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as either being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beacon Supergroup
The Beacon Supergroup is a geological formation exposed in Antarctica and deposited from the Devonian to the Triassic (). The unit was originally described as either a formation or sandstone, and upgraded to group and supergroup as time passed. It contains a sandy member known as the Beacon Heights Orthoquartzite. Overview The base of the Beacon Supergroup is marked by an unconformity and is composed of the Devonian Taylor Group, a quartzose sandstone sequence; and the Late Carboniferous to Early Jurassic Victoria Group, consisting of glacial beds, sandstone, shale, conglomerate, and coal. The Beacon Sandstone was named by Hartley T. Ferrar during Scott's Discovery Expedition (1901–1904), using the Beacon Heights survey points as reference. ''Glossopteris'' fossils dated the sandstone to the Permian and linked the lithology to similar sequences on neighboring continents. Generally flat lying, the supergroup is up to 3.2 km thick and is fairly continuous from south Victor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian reptiles, like the dinosaurs; an abundance of conifers and ferns; a hot Greenhouse and icehouse earth, greenhouse climate; and the tectonic break-up of Pangaea. The Mesozoic is the middle of the three eras since Cambrian explosion, complex life evolved: the Paleozoic, the Mesozoic, and the Cenozoic. The era began in the wake of the Permian–Triassic extinction event, the largest well-documented mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction whose victims included the non-avian dinosaurs, Pterosaur, pterosaurs, Mosasaur, mosasaurs, and Plesiosaur, plesiosaurs. The Mesozoic was a time of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ''zōḗ'' (), "life", meaning "ancient life" ). It is the longest of the Phanerozoic eras, lasting from , and is subdivided into six geologic periods (from oldest to youngest): # Cambrian # Ordovician # Silurian # Devonian # Carboniferous # Permian The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion, in which most modern phyla first appeared. Arthropods, molluscs, fish, amphibians, reptiles, and synapsids all evolved during the Paleozoic. Life began in the ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sill (geology)
In geology, a sill is a tabular sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava or tuff, or along the direction of foliation in metamorphic rock. A ''sill'' is a ''concordant intrusive sheet'', meaning that a sill does not cut across preexisting rock beds. Stacking of sills builds a sill complex . and a large magma chamber at high magma flux. In contrast, a dike is a discordant intrusive sheet, which does cut across older rocks. Sills are fed by dikes, except in unusual locations where they form in nearly vertical beds attached directly to a magma source. The rocks must be brittle and fracture to create the planes along which the magma intrudes the parent rock bodies, whether this occurs along preexisting planes between sedimentary or volcanic beds or weakened planes related to foliation in metamorphic rock. These planes or weakened areas allow the intrusion of a thin sheet-like body of magma paralleling the existing bedding pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolerite
Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grained to aphanitic chilled margins which may contain tachylite (dark mafic glass). ''Diabase'' is the preferred name in North America, while ''dolerite'' is the preferred name in the rest of the English-speaking world, where sometimes the name ''diabase'' refers to altered dolerites and basalts. Some geologists prefer to avoid confusion by using the name ''microgabbro''. The name ''diabase'' comes from the French ', and ultimately from the Greek - meaning "act of crossing over, transition". Petrography Diabase normally has a fine but visible texture of euhedral lath-shaped plagioclase crystals (62%) set in a finer matrix of clinopyroxene, typically augite (20–29%), with minor olivine (3% up to 12% in olivine diabase), magnetite (2%), and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trio Nunataks
The Prince Albert Mountains () are a major mountain group in Antarctica over 320 km (200 mi) long. Located in Victoria Land, they run north–south between the Priestley and Ferrar glaciers. They were named for Prince Albert, the consort of the British Queen Victoria. Although they were discovered by Sir James Clark Ross on February 17, 1841, they were not first explored until the early 1900s, when British cartographers came. They were mapped and surveyed carefully by explorers from the United States and New Zealand in the 1950s and 1960s. Major peaks This range include the following mountains: Other features Other features or groups of features in the Prince Albert Mountains have been named by various survey groups and expeditions. Sheppard Rocks () is a group of rocks first mapped by United States Geological Survey (USGS) from surveys and U.S. Navy air photos, 1956–62. Named by Advisory Committee on Antarctic Names (US-ACAN) for Paul D. Sheppard, storekeep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Howard (Antarctica)
Mount Joyce is a prominent, dome-shaped mountain, high, standing on the south side of David Glacier, northwest of Mount Howard in the Prince Albert Mountains of Victoria Land, Antarctica. It was first mapped by the British Antarctic Expedition, 1907–09, which named it for Ernest Joyce who was in charge of general stores, dogs, sledges, and zoological collections with the expedition and who had earlier been with the British National Antarctic Expedition, 1901–04. Joyce was also with the Ross Sea party of Shackleton's Imperial Trans-Antarctic Expedition, 1914–17. Geology Mount Joyce, along with nearby nunataks, such as the Trio Nunataks, represents the remnants of a tableland of the Jurassic Ferrar Group, which consists of Kirkpatrick lavas and Ferrar dolerite sills, alternating with rafts of sandstone of the Paleozoic and Mesozoic Beacon Supergroup. The strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by cer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saunders_Quarry-1.jpg "Click for more on -> Sandstone")
