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Cape Purvis
Cape Purvis () is a cape forming the south extremity of Dundee Island, off the north tip of Antarctic Peninsula. Its topography is that of a promontory which forms a mesa. The rest of the island is smooth. Composition The only large, accessible portion of Cape Purvis is at its southwest. It is composed of recently-formed volcanic rock of the James Ross Island Volcanic Group. Cape Purvis is described as a basalt tuya in the ''Encyclopedia of Quaternary Science''. The basalts on Cape Purvis have similar composition to lavas on Paulet Island, which is 5 kilometers east of it. Said composition is relatively low in magnesium oxide but high in titanium dioxide, calcium oxide, and niobium. Cape Purvis's snow and ice-covered summit boasts an unnamed hill at its northern edge. Discovery It was discovered in December 1842 by Captain James Ross, Royal Navy, and named by him for Commodore (later Rear Admiral Rear admiral is a senior naval flag officer rank, equivalent to a maj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dundee Island
Dundee Island is an ice-covered island lying east of the northeastern tip of Antarctic Peninsula and south of Joinville Island. It is named after the city of Dundee in Scotland. The Petrel Base is a scientific station in Antarctica belonging to Argentina. Its coordinates are 63 ° 28′S 56 ° 17′W and it is located on rocks at 18 meters above sea level at the foot of the Rosamaría glacier in the Petrel bay, the low point of Cape Welchness on Dundee Island in the Joinville archipelago. A 10-year plan began in 2013 to convert it into a permanent base. The base infrastructure has 3600 m² under roof, a 1200 m² logistics area and 25 beds. Account for transport: 2 Zodiac with outboard motor and 1 all-terrain truck of 1.5 ton. It is from this island that the American businessman Lincoln Ellsworth, accompanied by the pilot Herbert Hollick-Kenyon, took off on the 23 November 1935 for the first crossing of the Antarctic by plane. Nearby features The Eden Rocks, a designated Im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Peninsula
The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martín in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica. The Antarctic Peninsula is part of the larger peninsula of West Antarctica, protruding from a line between Cape Adams (Weddell Sea) and a point on the mainland south of the Eklund Islands. Beneath the ice sheet that covers it, the Antarctic Peninsula consists of a string of bedrock islands; these are separated by deep channels whose bottoms lie at depths considerably below current sea level. They are joined by a grounded ice sheet. Tierra del Fuego, the southernmost tip of South America, is about away across the Drake Passage. The Antarctic Peninsula is in area and 80% ice-covered. The marine ecosystem around the western continental shelf of the Antarctic Peninsula (WAP) has been subjected to rapid climate change. Over the past 50 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promontory
A promontory is a raised mass of land that projects into a lowland or a body of water (in which case it is a peninsula). Most promontories either are formed from a hard ridge of rock that has resisted the erosive forces that have removed the softer rock to the sides of it, or are the high ground that remains between two river valleys where they form a confluence. A headland, or head, is a type of promontory. Promontories in history Located at the edge of a landmass, promontories offer a natural defense against enemies, as they are often surrounded by water and difficult to access. Many ancient and modern forts and castles have been built on promontories for this reason. One of the most famous examples of promontory forts is the Citadel of Namur in Belgium. Located at the confluence of the Meuse and Sambre rivers, the citadel has been a prime fortified location since the 10th century. The surrounding rivers act as a natural moat, making it difficult for enemies to access th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesa
A mesa is an isolated, flat-topped elevation, ridge or hill, which is bounded from all sides by steep escarpments and stands distinctly above a surrounding plain. Mesas characteristically consist of flat-lying soft sedimentary rocks capped by a more resistant layer or layers of harder rock, e.g. shales overlain by sandstones. The resistant layer acts as a caprock that forms the flat summit of a mesa. The caprock can consist of either sedimentary rocks such as sandstone and limestone; dissected lava flows; or a deeply eroded duricrust. Unlike ''plateau'', whose usage does not imply horizontal layers of bedrock, e.g. Tibetan Plateau, the term ''mesa'' applies exclusively to the landforms built of flat-lying strata. Instead, flat-topped plateaus are specifically known as '' tablelands''.Duszyński, F., Migoń, P. and Strzelecki, M.C., 2019. ''Escarpment retreat in sedimentary tablelands and cuesta landscapes–Landforms, mechanisms and patterns.'' ''Earth-Science Reviews, no. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Ross Island Volcanic Group
The James Ross Island Volcanic Group is a stratigraphic unit of Cenozoic age distributed on James Ross Island and Vega Island of the James Ross Island group, the Tabarin and Trinity peninsulas of Graham Land and surrounding islands in the Prince Gustav and Antarctic sounds. The volcanic group consists predominantly of alkali basalts with minor hawaiites, benmoreites and mugearites. They are interpreted to have been deposited by volcanic eruptions in an extensional back-arc setting after subduction had ceased along the western margin of the Antarctic Peninsula. K–Ar dating of these rocks suggest that they were erupted from about 7 million years ago up until about a few hundred thousand years ago. However, volcanic rocks as young as only a few thousand years old may exist on James Ross Island. Rocks of the James Ross Island Volcanic Group comprise Surtseyan tuff cones and Strombolian cinder cones, as well as lava deltas and overlying subaerial lava flows. The dominating fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuya
A tuya is a flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are rare worldwide, being confined to regions which were covered by glaciers and had active volcanism during the same period. As lava that erupts under a glacier cools very quickly and cannot travel far, it piles up into a steep-sided hill. If the eruption continues long enough, it either melts all the ice or emerges through the top of the ice and then creates normal-looking lava flows that make a flat cap on top of the hill. Discovering and dating the lava flows in a tuya has proven useful in reconstructing past glacial ice extents and thicknesses. Formation Tuyas are a type of subglacial volcano that consists of nearly horizontal beds of lava capping outward-dipping beds of fragmental volcanic rocks, and they often rise in isolation above a surrounding plateau. Tuyas are found in Iceland, British Columbia, the Santiam Pass region in Oregon, the Tyva Republic in eas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paulet Island
Paulet Island is a circular island about in diameter, lying south-east of Dundee Island, off the north-eastern end of the Antarctic Peninsula. Because of its large penguin colony, it is a popular destination for sightseeing tours. Description The island is composed of lava flows capped by a cinder cone with a small summit crater. Geothermal heat keeps parts of the island ice-free, and the youthful morphology of the volcano suggests that it was last active within the last 1,000 years. The island is part of the James Ross Island Volcanic Group. Historic monuments Paulet Island was discovered by a British expedition (1839–1843) under James Clark Ross and named by him for Captain the Right Honorable Lord George Paulet, Royal Navy. In 1903 during the Swedish Antarctic Expedition led by Otto Nordenskiöld his ship ''Antarctic'' was crushed and sunk by the ice off the coast of the island. A stone hut built in February 1903 by shipwreck survivors, together with the grave of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Clark Ross
Sir James Clark Ross (15 April 1800 – 3 April 1862) was a British Royal Navy officer and polar explorer known for his explorations of the Arctic, participating in two expeditions led by his uncle John Ross, and four led by William Edward Parry, and, in particular, for his own Antarctic expedition from 1839 to 1843. Biography Early life Ross was born in London, the son of George Ross and nephew of John Ross, under whom he entered the Royal Navy on 5 April 1812. Ross was an active participant in the Napoleonic Wars, being present at an action where HMS ''Briseis'', commanded by his uncle, captured ''Le Petit Poucet'' (a French privateer) on 9 October 1812. Ross then served successively with his uncle on HMS ''Actaeon'' and HMS ''Driver''. Arctic exploration Ross participated in John's unsuccessful first Arctic voyage in search of a Northwest Passage in 1818 aboard ''Isabella''. Between 1819 and 1827 Ross took part in four Arctic expeditions under William Ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against France. The modern Royal Navy traces its origins to the early 16th century; the oldest of the UK's armed services, it is consequently known as the Senior Service. From the middle decades of the 17th century, and through the 18th century, the Royal Navy vied with the Dutch Navy and later with the French Navy for maritime supremacy. From the mid 18th century, it was the world's most powerful navy until the Second World War. The Royal Navy played a key part in establishing and defending the British Empire, and four Imperial fortress colonies and a string of imperial bases and coaling stations secured the Royal Navy's ability to assert naval superiority globally. Owing to this historical prominence, it is common, even among non-Britons, to ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rear Admiral
Rear admiral is a senior naval flag officer rank, equivalent to a major general and air vice marshal and above that of a commodore and captain, but below that of a vice admiral. It is regarded as a two star "admiral" rank. It is often regarded as a two-star rank with a NATO code of OF-7. The term originated in the days of naval sailing squadrons and can trace its origins to the Royal Navy. Each naval squadron was assigned an admiral as its head, who commanded from the centre vessel and directed the squadron's activities. The admiral would in turn be assisted by a vice admiral, who commanded the lead ships that bore the brunt of a battle. In the rear of the squadron, a third admiral commanded the remaining ships and, as this section was considered to be in the least danger, the admiral in command of it was typically the most junior. This has continued into the modern age, with rear admiral the most junior admiralty of many navies. In most European navies, the equivalent rank i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John B
John Bryn Williams (born 1977), known as John B, is an English disc jockey and electronic music producer. He is widely recognised for his eccentric clothing and wild hair and his production of several cutting edge drum and bass tracks. John B ranked number 76 in ''DJ Magazine''s 2010 Top 100 DJs annual poll, announced on 27 October 2010. Career Williams was born on 12 July 1977 in Maidenhead, Berkshire. He started producing music around the age of 14, and now is the head of drum and bass record label Beta Recordings, together with its more specialist drum and bass sub-labels Nu Electro, Tangent, and Chihuahua. He also has releases on Formation Records, Metalheadz and Planet Mu. Williams was ranked 92nd drum and bass DJ on the 2009 ''DJ Magazine'' top 100. Style While his trademark sound has evolved through the years, it generally involves female vocals and trance-like synths (a style which has been dubbed "trance and bass", "trancestep" and "futurestep" by listeners). His m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
