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Shirasu-Daichi
is a broad pyroclastic plateau in southern Japan. It covers almost all of southern Kyūshū, which was formed by pyroclastic flows. It covers more than half of Kagoshima Prefecture, as well as 16% of Miyazaki Prefecture.寺園貞夫 「シラスの堆積とその浸食地形」 『シラス台地研究』 The Japanese Shirasu (シラス) is a local name of the pumiceous sediments in Kagoshima Prefecture, Japan. The term has been recommended to be used just for the non-welded ignimbrite component in the Japanese geological literature. Daichi (台地) means plateau. Geology A major three phase eruption of the Aira Caldera formed in the first phase the Osumi pumice fall, had a second phase Tsumaya pyroclastic flow and in the third Ito eruption phase produced the widely distributed Aira-Tn tephra that has been dated at 29,428 to 30,148 years calibrated before present. The Aira-Tn tephra falls from this eruption were up to thick extending to significant depth that would hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Plateau
A volcanic plateau is a plateau produced by volcanic activity. There are two main types: lava plateaus and pyroclastic plateaus. Lava plateau Lava plateaus are formed by highly fluid basaltic lava during numerous successive eruptions through numerous vents without violent explosions (quiet eruptions). These eruptions are quiet because of low viscosity of lava, so that it is very fluid and contains a small amount of trapped gases. The resulting sheet lava flows may be extruded from linear fissures or rifts or gigantic volcanic eruptions through multiple vents characteristic of the prehistoric era which produced giant flood basalts. Multiple successive and extensive lava flows cover the original landscape to eventually form a plateau, which may contain lava fields, cinder cones, shield volcanoes and other volcanic landforms. In some cases, a lava plateau may be part of a single volcano. An example is the massive Level Mountain shield volcano in northern British Columbia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aira Caldera
Aira Caldera is a gigantic volcanic caldera that is located on the southern end of Kyushu, Japan. It is believed to have been formed about 30,000 years ago with a succession of pyroclastic surges. It is currently the place of residence to over 900,000 people. The shores of Aira Caldera are home to rare flora and fauna, including Japanese bay tree and Japanese black pine. The caldera is home to Mount Sakurajima, and the Mount Kirishima group of stratovolcanoes lies to the north of the caldera. The most famous and active of this group is Shinmoedake. Aira Caldera has an underlying magmatic chamber that connects with the Kirishima magmatic system. This has enabled magma from the caldera to feed into the stratovolcano Sakurajima, causing it to expand over time. Thus, Sakurajima has caused a series of disasters such as the eruption in 1914 which killed 58 people and sank the magma chamber by 60cm. History Location Aira caldera is located at Kyushu, the southernmost island of J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Plateau
A volcanic plateau is a plateau produced by volcanic activity. There are two main types: lava plateaus and pyroclastic plateaus. Lava plateau Lava plateaus are formed by highly fluid basaltic lava during numerous successive eruptions through numerous vents without violent explosions (quiet eruptions). These eruptions are quiet because of low viscosity of lava, so that it is very fluid and contains a small amount of trapped gases. The resulting sheet lava flows may be extruded from linear fissures or rifts or gigantic volcanic eruptions through multiple vents characteristic of the prehistoric era which produced giant flood basalts. Multiple successive and extensive lava flows cover the original landscape to eventually form a plateau, which may contain lava fields, cinder cones, shield volcanoes and other volcanic landforms. In some cases, a lava plateau may be part of a single volcano. An example is the massive Level Mountain shield volcano in northern British Columbia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kyushu
is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surrounding islands. Kyushu has a land area of and a population of 14,311,224 in 2018. In the 8th-century Taihō Code reforms, Dazaifu was established as a special administrative term for the region. Geography The island is mountainous, and Japan's most active volcano, Mount Aso at , is on Kyushu. There are many other signs of tectonic activity, including numerous areas of hot springs. The most famous of these are in Beppu, on the east shore, and around Mt. Aso in central Kyushu. The island is separated from Honshu by the Kanmon Straits. Being the nearest island to the Asian continent, historically it is the gateway to Japan. The total area is which makes it the 37th largest island in the world. It's slightly larger than Taiwan island . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north toward the East China Sea, Philippine Sea, and Taiwan in the south. Japan is a part of the Ring of Fire, and spans Japanese archipelago, an archipelago of List of islands of Japan, 6852 islands covering ; the five main islands are Hokkaido, Honshu (the "mainland"), Shikoku, Kyushu, and Okinawa Island, Okinawa. Tokyo is the Capital of Japan, nation's capital and largest city, followed by Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, Kobe, and Kyoto. Japan is the List of countries and dependencies by population, eleventh most populous country in the world, as well as one of the List of countries and dependencies by population density, most densely populated and Urbanization by country, urbanized. About three-fourths of Geography of Japan, the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ignimbrite
Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surrounding atmosphere. New Zealand geologist Patrick Marshall (1869-1950) coined the term ''ignimbrite'' from the Latin ''igni-'' [fire] and ''imbri-'' [rain]. Ignimbrites are made of a very poorly sorted mixture of volcanic ash (or tuff when Lithification, lithified) and pumice lapilli, commonly with scattered lithic fragments. The ash is composed of glass shards and crystal fragments. Ignimbrites may be loose and unconsolidated, or lithified (solidified) rock called lapilli-tuff. Near the volcanic source, ignimbrites often contain thick accumulations of lithic blocks, and distally, many show meter-thick accumulations of rounded cobbles of pumice. Ignimbrites may be white, grey, pink, beige, brown, or black depending on their composition and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kyūshū
is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surrounding islands. Kyushu has a land area of and a population of 14,311,224 in 2018. In the 8th-century Taihō Code reforms, Dazaifu was established as a special administrative term for the region. Geography The island is mountainous, and Japan's most active volcano, Mount Aso at , is on Kyushu. There are many other signs of tectonic activity, including numerous areas of hot springs. The most famous of these are in Beppu, on the east shore, and around Mt. Aso in central Kyushu. The island is separated from Honshu by the Kanmon Straits. Being the nearest island to the Asian continent, historically it is the gateway to Japan. The total area is which makes it the 37th largest island in the world. It's slightly larger than Taiwan island . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroclastic Flow
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of but is capable of reaching speeds up to . The gases and tephra can reach temperatures of about . Pyroclastic flows are the most deadly of all volcanic hazards and are produced as a result of certain explosive eruptions; they normally touch the ground and hurtle downhill, or spread laterally under gravity. Their speed depends upon the density of the current, the volcanic output rate, and the gradient of the slope. Origin of term The word ''pyroclast'' is derived from the Greek (''pýr''), meaning "fire", and (''klastós''), meaning "broken in pieces". A name for pyroclastic flows which glow red in the dark is (French, "burning cloud"); this was notably used to describe the disastrous 1902 eruption of Mount Pelée on Martinique, a French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kagoshima Prefecture
is a prefecture of Japan located on the island of Kyushu and the Ryukyu Islands. Kagoshima Prefecture has a population of 1,599,779 (1 January 2020) and has a geographic area of 9,187 km2 (3,547 sq mi). Kagoshima Prefecture borders Kumamoto Prefecture to the north and Miyazaki Prefecture to the northeast. Kagoshima is the capital and largest city of Kagoshima Prefecture, with other major cities including Kirishima, Kanoya, and Satsumasendai. Kagoshima Prefecture is located at the southernmost point of Kyūshū and includes the Satsunan Islands group of the Ryukyu Islands. Kagoshima Prefecture's mainland territory extends from the Ariake Sea to Shibushi Bay on the Pacific Ocean coast, and is characterized by two large peninsulas created by Kagoshima Bay. Kagoshima Prefecture formed the core of the Satsuma Domain, ruled from Kagoshima Castle, one of the most important Japanese domains of the Edo period and the Meiji Restoration. History Kagoshima Prefecture correspo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miyazaki Prefecture
is a prefecture of Japan located on the island of Kyūshū. Miyazaki Prefecture has a population of 1,073,054 (1 June 2019) and has a geographic area of 7,735 km2 (2,986 sq mi). Miyazaki Prefecture borders Ōita Prefecture to the north, Kumamoto Prefecture to the northwest, and Kagoshima Prefecture to the southwest. Miyazaki is the capital and largest city of Miyazaki Prefecture, with other major cities including Miyakonojō, Nobeoka, and Hyūga. Miyazaki Prefecture is located in southeastern Kyūshū on Japan's Pacific coast, with its coastline extending from Nobeoka near the entrance to the Bungo Channel to Shibushi Bay in Kushima. History Historically, after the Meiji Restoration, Hyūga Province was renamed Miyazaki Prefecture. In Japan, Miyazaki Prefecture was first created in 1873 when Mimitsu Prefecture was merged with parts of Miyakonojō Prefecture. The first Miyazaki existed only until 1876 when it was merged (back) into Kagoshima Prefecture. Under publ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ignimbrite
Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surrounding atmosphere. New Zealand geologist Patrick Marshall (1869-1950) coined the term ''ignimbrite'' from the Latin ''igni-'' [fire] and ''imbri-'' [rain]. Ignimbrites are made of a very poorly sorted mixture of volcanic ash (or tuff when Lithification, lithified) and pumice lapilli, commonly with scattered lithic fragments. The ash is composed of glass shards and crystal fragments. Ignimbrites may be loose and unconsolidated, or lithified (solidified) rock called lapilli-tuff. Near the volcanic source, ignimbrites often contain thick accumulations of lithic blocks, and distally, many show meter-thick accumulations of rounded cobbles of pumice. Ignimbrites may be white, grey, pink, beige, brown, or black depending on their composition and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pumice
Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicular volcanic rock that differs from pumice in having larger vesicles, thicker vesicle walls, and being dark colored and denser.Jackson, J.A., J. Mehl, and K. Neuendorf (2005) ''Glossary of Geology'' American Geological Institute, Alexandria, Virginia. 800 pp. McPhie, J., M. Doyle, and R. Allen (1993) ''Volcanic Textures A guide to the interpretation of textures in volcanic rocks'' Centre for Ore Deposit and Exploration Studies, University of Tasmania, Hobart, Tasmania..198 pp. Pumice is created when super-heated, highly pressurized rock is violently ejected from a volcano. The unusual foamy configuration of pumice happens because of simultaneous rapid cooling and rapid depressurization. The depressurization creates bubbles by lowering the solubi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
