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Long Island (Papua New Guinea)
Long Island is a volcanic island in Papua New Guinea. It is located north of the island of New Guinea, separated from it by the Vitiaz Strait. Geography Two stratovolcanoes are located on the island: Mount Reaumur and Cerisy Peak. The summit of the volcanic complex collapsed during at least three major explosive eruptions, about 16,000, 4000, and 300 years ago. These produced a large caldera 10 x 12.5 km in size, now filled with a freshwater crater lake, Lake Wisdom. In 1953-1954 and 1968, volcanic activity created Motmot Island on the crater lake, 200 x 200 m in size. The 1660 eruption was one of the largest in Papua New Guinea's recent history with an estimated air-fall volume in excess of 11 cu km, comparable to the 1991 eruption of Mount Pinatubo, but the Global Volcanism Program gives a much higher estimate of 30 cu km. This cataclysmic event prompted legends of a "Time of Darkness". The most recent (and a smaller) eruption occurred in 1993. The crater holds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papua New Guinea
Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country in Oceania that comprises the eastern half of the island of New Guinea and its offshore islands in Melanesia (a region of the southwestern Pacific Ocean north of Australia). Its capital, located along its southeastern coast, is Port Moresby. The country is the world's third largest island country, with an area of . At the national level, after being ruled by three external powers since 1884, including nearly 60 years of Australian administration starting during World War I, Papua New Guinea established its sovereignty in 1975. It became an independent Commonwealth realm in 1975 with Elizabeth II as its queen. It also became a member of the Commonwealth of Nations in its own right. There are 839 known languages of Papua New Guinea, one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imperial Japanese
The also known as the Japanese Empire or Imperial Japan, was a historical nation-state and great power that existed from the Meiji Restoration in 1868 until the enactment of the post-World War II 1947 constitution and subsequent formation of modern Japan. It encompassed the Japanese archipelago and several colonies, protectorates, mandates, and other territories. Under the slogans of and following the Boshin War and restoration of power to the Emperor from the Shogun, Japan underwent a period of industrialization and militarization, the Meiji Restoration, which is often regarded as the fastest modernisation of any country to date. All of these aspects contributed to Japan's emergence as a great power and the establishment of a colonial empire following the First Sino-Japanese War, the Boxer Rebellion, the Russo-Japanese War, and World War I. Economic and political turmoil in the 1920s, including the Great Depression, led to the rise of militarism, nationalism and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Crater Lakes
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calderas Of Papua New Guinea
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is gone. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface (from one to dozens of kilometers in diameter). Although sometimes described as a Volcanic crater, crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur each century, the formation of a caldera is a rare event, occurring only a few times per century. Only seven caldera-forming collapses are known to have occurred between 1911 and 2016. More recently, a caldera collapse occurred at Kīlauea, Hawaii in 2018. Etymology The term ''caldera'' comes from Spanish language, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Volcanoes
An active volcano is a volcano which is either erupting or is likely to erupt in the future. An active volcano which is not currently erupting is known as a dormant volcano. Overview Tlocene Epoch. Most volcanoes are situated on the Pacific Ring of Fire. An estimated 500 million people live near active volcanoes. ''Historical time'' (or recorded history) is another timeframe for ''active''. However, the span of recorded history differs from region to region. In China and the Mediterranean, it reaches back nearly 3,000 years, but in the Pacific Northwest of the United States and Canada, it reaches back less than 300 years, and in Hawaii and New Zealand it is only around 200 years. The incomplete ''Catalogue of the Active Volcanoes of the World'', published in parts between 1951 and 1975 by the International Association of Volcanology, uses this definition, by which there are more than 500 active volcanoes. , the Smithsonian Global Volcanism Program recognizes 560 volcanoes with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcanoes Of Papua New Guinea
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volcanoes. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Islands Of Papua New Guinea
An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island in a river or a lake island may be called an eyot or ait, and a small island off the coast may be called a holm. Sedimentary islands in the Ganges delta are called chars. A grouping of geographically or geologically related islands, such as the Philippines, is referred to as an archipelago. There are two main types of islands in the sea: continental and oceanic. There are also artificial islands, which are man-made. Etymology The word ''island'' derives from Middle English ''iland'', from Old English ''igland'' (from ''ig'' or ''ieg'', similarly meaning 'island' when used independently, and -land carrying its contemporary meaning; cf. Dutch ''eiland'' ("island"), German ''Eiland'' ("small island")). However, the spelling of the word ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of Volcanism On Earth
This timeline of volcanism on Earth includes a list of major volcanic eruptions of approximately at least magnitude 6 on the Volcanic explosivity index (VEI) or equivalent sulfur dioxide emission during the Quaternary period (from 2.58 Mya to the present). Other volcanic eruptions are also listed. Some eruptions cooled the global climate—inducing a volcanic winter—depending on the amount of sulfur dioxide emitted and the magnitude of the eruption. Before the present Holocene epoch, the criteria are less strict because of scarce data availability, partly since later eruptions have destroyed the evidence. Only some eruptions before the Neogene period (from 23 Mya to 2.58 Mya) are listed. Known large eruptions after the Paleogene period (from 66 Mya to 23 Mya) are listed, especially those relating to the Yellowstone hotspot, the Santorini caldera, and the Taupō Volcanic Zone. Active volcanoes such as Stromboli, Mount Etna and Kīlauea do not appear on this list, but some back- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Volcanoes In Papua New Guinea ...
This is a list of active and extinct volcanoes in Papua New Guinea. New Guinea Admiralty Islands Bougainville D'Entrecasteaux Islands New Britain New Ireland Offshore islands References * Volcanoes of the World External links * {{Global Volcanism Program Papua New Guinea * Volcanoes A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Australian Air Force
"Through Adversity to the Stars" , colours = , colours_label = , march = , mascot = , anniversaries = RAAF Anniversary Commemoration – 31 March , equipment = , equipment_label = , battles = * Second World War * Berlin Airlift * Korean War * Malayan Emergency * Indonesia–Malaysia Confrontation * Vietnam War * Operation Astute, East Timor * War in Afghanistan (2001–present), War in Afghanistan * Iraq War * American-led intervention in Iraq (2014–present), Military intervention against ISIL , decorations = , battle_honours = , battle_honours_label = , flying_hours = , website = , commander1 = Governor-General of Australia, Governor-General David Hurley as representative of Charles III as Monarchy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of Cape Gloucester
The Battle of Cape Gloucester was fought in the Pacific theater of World War II between Japanese and Allied forces on the island of New Britain, Territory of New Guinea, between 26 December 1943 and 16 January 1944. Codenamed Operation Backhander, the US landing formed part of the wider Operation Cartwheel, the main Allied strategy in the South West Pacific Area and Pacific Ocean Areas during 1943–1944. It was the second landing the US 1st Marine Division had conducted during the war thus far, after Guadalcanal. The objective of the operation was to capture the two Japanese airfields near Cape Gloucester that were defended by elements of the Japanese 17th Division. The main landing came on 26 December 1943, when US Marines landed on either side of the peninsula. The western landing force acted as a diversion and cut the coastal road near Tauali to restrict Japanese freedom of movement, while the main force, landing on the eastern side, advanced north towards the airfields. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Station
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving information about the objects' locations and speeds. Radar was developed secretly for military use by several countries in the period before and during World War II. A key development was the cavity magnetron in the United Kingdom, which allowed the creation of relatively small systems with sub-meter resolution. The t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
