located_in_the_administrative_territorial_entity ukinrek maars
Unimak Island is the largest island in the Aleutian Islands chain ___MASK95___ the U . S . state ___MASK95___ ___MASK46___ . Magnesium is a chemical element with symbol Mg and atomic number 12 . It is a shiny ___MASK90___ solid which bears a close physical resemblance to the other five elements in the second column ( Group 2 , or alkaline ___MASK28___ metals ) ___MASK95___ the periodic table : all Group 2 elements have the same electron configuration in the outer electron shell and a similar crystal structure . A ___MASK67___ range ( also ___MASK67___ barrier , belt , or system ) is a geographic area containing numerous geologically related mountains . A ___MASK67___ system or system ___MASK95___ ___MASK67___ ranges , sometimes is used to combine several geological features that are geographically ( regionally ) related . On Earth , most significant ___MASK67___ ranges are the result ___MASK95___ plate tectonics , though ___MASK67___ ranges are formed by a range ___MASK95___ processes , are found on many planetary mass objects in the Solar System and are likely a feature ___MASK95___ most terrestrial planets . ___MASK47___ is a United States National Park and Preserve in southern ___MASK46___ , notable for the Valley of Ten Thousand Smokes and for its Alaskan brown bears . The park and preserve covers , being roughly the size of Wales . Most of this is a designated wilderness area in the national park where all hunting is banned , including over of land . The park is named after Mount Katmai , its centerpiece stratovolcano . The park is located on the ___MASK46___ Peninsula , across from Kodiak Island , with headquarters in nearby King Salmon , about southwest of Anchorage . The area was first designated a national monument in 1918 to protect the area around the major 1912 volcanic eruption of Novarupta , which formed the Valley of Ten Thousand Smokes , a , pyroclastic flow . The park includes as many as 18 individual volcanoes , seven of which have been active since 1900 . A flood basalt is the result ___MASK95___ a giant volcanic eruption or series ___MASK95___ eruptions that coats large stretches ___MASK95___ land or the ocean floor with basalt lava . Flood basalt provinces such as the Deccan Traps ___MASK95___ India are often called traps , which derives from the characteristic stairstep geomorphology ___MASK95___ many associated landscapes . Rampino and Stothers ( 1988 ) cite eleven distinct flood basalt episodes occurring in the past 250 million years , creating large volcanic provinces , plateaus , and mountain ranges . However , more have been recognized such as the large Ontong Java Plateau , and the Chilcotin Group , though the latter may be linked to the Columbia River Basalt Group . Large igneous provinces have been connected to five mass extinction events , and may be associated with bolide impacts . An explosion is a rapid increase in volume and release ___MASK95___ energy in an extreme manner , usually with the generation ___MASK95___ high temperatures and the release ___MASK95___ gases . Supersonic explosions created by high explosives are known as detonations and travel via supersonic shock waves . Subsonic explosions are created by low explosives through a slower burning process known as deflagration . When caused by a man - made device such as an exploding rocket or firework , the audible component ___MASK95___ an explosion is referred to as its " report " ( which can also be used as a verb , e . g ., " the rocket reported loudly upon impact ".) The ___MASK80___ is the largest ___MASK95___ the Earth ' s oceanic divisions . It extends from the Arctic Ocean in the north to the Southern Ocean ( or , depending on definition , to Antarctica ) in the south and is bounded by Asia and Australia in the west and the Americas in the east . Lava is the molten ___MASK11___ expelled by a volcano during an eruption . The resulting ___MASK11___ after solidification and cooling is also called " lava ". The molten ___MASK11___ is formed in the interior ___MASK95___ some planets , including Earth , and some ___MASK95___ their satellites . The source ___MASK95___ the heat that melts the ___MASK11___ within the earth is geothermal energy . When first erupted from a volcanic vent , lava is a liquid usually at temperatures from . The Aleutian Arc is a large volcanic arc in the U . S . state ___MASK95___ ___MASK46___ . It consists ___MASK95___ a number ___MASK95___ active and dormant volcanoes that have formed as a result ___MASK95___ subduction along the Aleutian Trench . Although taking its name from the Aleutian Islands , this term is a geologic grouping rather than a geographic one , and the Aleutian Arc extends through the ___MASK46___ Peninsula following the Aleutian Range to the Aleutian Islands . Groundwater ( or ground water ) is the water present beneath ___MASK28___ ' s surface in soil pore spaces and in the fractures ___MASK95___ rock formations . A unit ___MASK95___ rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity ___MASK95___ water . The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table . Groundwater is recharged from , and eventually flows to , the surface naturally ; natural discharge often occurs at springs and seeps , and can form oases or wetlands . Groundwater is also often withdrawn for agricultural , municipal , and industrial use by constructing and operating extraction wells . The study ___MASK95___ the distribution and movement ___MASK95___ groundwater is hydrogeology , also called groundwater hydrology . The ___MASK46___ Peninsula is a peninsula extending about to the southwest from the mainland of ___MASK46___ and ending in the Aleutian Islands . The peninsula separates the Pacific Ocean from Bristol Bay , an arm of the Bering Sea . A maar is a broad , low - relief volcanic crater caused by a phreatomagmatic eruption ( an explosion which occurs when groundwater comes into contact with ___MASK44___ lava or magma ). A maar characteristically fills with water to form a relatively shallow crater lake which may also be called a maar . The name comes from a Moselle Franconian dialect word used for the circular ___MASK76___ of the Daun area of Germany . Maars are shallow , flat - floored craters that scientists interpret as having formed above diatremes as a result of a violent expansion of magmatic gas or steam ; deep erosion of a maar presumably would expose a diatreme . Maars range in size from across and from deep ; most maars commonly fill with water to form natural ___MASK76___ . Most maars have low rims composed of a mixture of loose fragments of volcanic rocks and rocks torn from the walls of the diatreme . A lake is an area ___MASK95___ variable size filled with water , localized in a basin , that is surrounded by land , apart from any river or other outlet that serves to feed or drain the lake . ___MASK76___ lie on land and are not part ___MASK95___ the ocean , and therefore are distinct from lagoons , and are also larger and deeper than ponds , though there are no official or scientific definitions . ___MASK76___ can be contrasted with rivers or streams , which are usually flowing . Most ___MASK76___ are fed and drained by rivers and streams . A crater lake is a lake that forms in a volcanic crater or caldera , such as a maar ; less commonly and with lower association to the term a lake may form in an impact crater caused by a meteorite , or in an artificial explosion caused by humans . Sometimes ___MASK76___ which form inside calderas are called caldera ___MASK76___ , but often this distinction is not made . Crater ___MASK76___ covering active ( fumarolic ) volcanic vents are sometimes known as volcanic ___MASK76___ , and the water within them is often acidic , saturated with volcanic gases , and cloudy with a strong greenish color . For example , the crater lake of Kawah Ijen in Indonesia has a pH of under 0 . 5 . ___MASK76___ located in dormant or extinct volcanoes tend to have fresh water , and the water clarity in such ___MASK76___ can be exceptional due to the lack of inflowing streams and sediment . ___MASK46___ is a U . S . state located in the northwest extremity of North America . The Canadian administrative divisions of British Columbia and Yukon border the state to the east ; its most extreme western part is Attu Island ; it has a maritime border with Russia to the west across the Bering Strait . To the north are the Chukchi and Beaufort seas  the southern parts of the Arctic Ocean . The Pacific Ocean lies to the south and southwest . ___MASK46___ is the largest state in the United States by area , the 3rd least populous and the least densely populated of the 50 United States . Approximately half of ___MASK46___ ' s residents ( the total estimated at 738 , 432 by the U . S . Census Bureau in 2015 ) live within the Anchorage metropolitan area . ___MASK46___ ' s economy is dominated by the fishing , natural gas , and oil industries , resources which it has in abundance . Military bases and tourism are also a significant part of the economy . Iron is a chemical element with symbol Fe ( from ) and atomic number 26 . It is a metal in the first transition series . It is by mass the ___MASK41___ common element on ___MASK28___ , forming much ___MASK95___ ___MASK28___ ' s outer and inner core . It is the fourth ___MASK41___ common element in the ___MASK28___ ' s crust . Its abundance in rocky planets like ___MASK28___ is due to its abundant production by fusion in high - mass stars , where it is the last element to be produced with release ___MASK95___ energy before the violent collapse ___MASK95___ a supernova , which scatters the iron into space . Tephra is fragmental material produced by a volcanic eruption regardless ___MASK95___ composition , fragment size or emplacement mechanism . The Bering Sea is a marginal sea ___MASK95___ the Pacific Ocean . It comprises a deep water basin , which then rises through a narrow slope into the shallower water above the continental shelves . The Aleutian Range is a major ___MASK67___ range located in ___MASK69___ ___MASK46___ , and it extends from Chakachamna Lake ( 80 miles / 130 km ___MASK69___ of Anchorage ) to Unimak Island , which is at the tip of the ___MASK46___ Peninsula . It includes all of the mountains of the peninsula , and what makes it so special is its large number of active volcanoes , which are also part of the larger Aleutian Arc . The mainland part of the range is about 600 miles ( 1000 km ) long ; the Aleutian Islands are ( geologically ) a partially submerged western extension of the range that stretches for another 1 , 600 km ( 1000 mi ). However the official designation " Aleutian Range " includes only the mainland peaks and the peaks on Unimak Island . The range is almost entirely roadless wilderness , and Katmai National Park and Preserve , a large national park within the range , must be reached by boat or plane . A volcano is a rupture in the crust ___MASK95___ a planetary - mass object , such as Earth , that allows hot lava , volcanic ash , and gases to escape from a magma chamber below the surface . Phreatomagmatic eruptions are volcanic eruptions resulting from interaction between magma and water . They differ from exclusively magmatic eruptions and phreatic eruptions . Unlike phreatic eruptions , the products ___MASK95___ phreatomagmatic eruptions contain juvenile ( magmatic ) clasts . It is common for a large explosive eruption to have magmatic and phreatomagmatic components . Becharof Lake is a long lake on the ___MASK46___ Peninsula . It is located south - east of Egegik , in the Aleutian Range . Basalt (, , , or ) is a common extrusive igneous ( volcanic ) ___MASK11___ formed from the rapid cooling ___MASK95___ basaltic lava exposed at or very near the surface ___MASK95___ a planet or moon . Flood basalt describes the formation in a series ___MASK95___ lava basalt flows . The mineral olivine is a magnesium iron silicate with the formula ( Mg , Fe ) SiO . Thus it is a type ___MASK95___ nesosilicate or orthosilicate . It is a common mineral in the Earth ' s subsurface but weathers quickly on the surface . Wilderness or wildland is a natural environment on ___MASK28___ that has not been significantly modified by civilized human activity . It may also be defined as : " The most intact , undisturbed wild natural areas left on our planet  those last truly wild places that humans do not control and have not developed with roads , pipelines or other industrial infrastructure ." ___MASK33___ , officially the Federal Republic ___MASK95___ ___MASK33___ , is a federal parliamentary republic in central - western Europe . It includes 16 constituent states , covers an area ___MASK95___ , and has a largely temperate seasonal climate . With about 82 million inhabitants , ___MASK33___ is the most populous member state ___MASK95___ the European Union . After the United States , it is the second most popular immigration destination in the world . ___MASK33___ ' s capital and largest metropolis is Berlin . Other major cities include Hamburg , Munich , ___MASK77___ , Frankfurt , Stuttgart and Düsseldorf . The Moon is an astronomical body that orbits planet ___MASK28___ , being ___MASK28___ ' s only permanent natural satellite . It is the fifth - largest natural satellite in the Solar System , and the largest among planetary satellites relative to the size ___MASK95___ the planet that it orbits ( its primary ). Following Jupiter ' s satellite Io , the Moon is second - densest satellite among those whose densities are known . Magma ( from Ancient Greek  (" mágma ") meaning " thick unguent ") is a mixture ___MASK95___ molten or semi - molten rock , volatiles and solids that is found beneath the surface ___MASK95___ the Earth , and is expected to exist on other terrestrial planets and some natural satellites . Besides molten rock , magma may also contain suspended crystals , dissolved gas and sometimes gas bubbles . Magma often collects in magma chambers that may feed a volcano or solidify underground to form an intrusion . Magma is capable ___MASK95___ intruding into adjacent rocks ( forming igneous dikes and sills ), extrusion onto the surface as lava , and explosive ejection as tephra to form pyroclastic rock . A volcanic crater is a roughly circular depression in the ground caused by volcanic activity . It is typically a bowl - shaped feature within which occurs a vent or vents . During volcanic eruptions , molten magma and volcanic gases ___MASK31___ from an underground magma chamber , through a tube - shaped conduit , until they reach the crater ' s vent , from where the gases escape into the atmosphere and the magma is erupted as lava . A volcanic crater can be ___MASK95___ large dimensions , and sometimes ___MASK95___ great depth . During certain types ___MASK95___ explosive eruptions , a volcano ' s magma chamber may empty enough for an area above it to subside , forming a type ___MASK95___ larger crater known as a caldera . Volcanic ___MASK11___ ( often shortened to volcanics in scientific contexts ) is a ___MASK11___ formed from magma erupted from a volcano . In other words , it differs from other igneous ___MASK11___ by being ___MASK95___ volcanic origin . Like all ___MASK11___ types , the concept ___MASK95___ volcanic ___MASK11___ is artificial , and in nature volcanic rocks grade into hypabyssal and metamorphic rocks and constitute an important element ___MASK95___ some sediments and sedimentary rocks . For these reasons , in geology , volcanics and shallow hypabyssal rocks are not always treated as distinct . In the context ___MASK95___ Precambrian shield geology , the term " volcanic " is often applied to what are strictly metavolcanic rocks . The Ukinrek Maars are two phreatomagmatic vents that formed on the ___MASK86___ side ___MASK95___ the Aleutian Range on a low area bordering the Bering Sea . The maars are 1 . 5 km south ___MASK95___ Becharof Lake and 12 km northwest ___MASK95___ Peulik Volcano . The western ___MASK95___ the two is elliptical in shape and up to 170 m in diameter and 35 m deep . The east maar lies 600 m to the east and is circular and up to 300 m in diameter and 70 m deep . The east maar has a 49 m - high lava dome within the crater lake . The eruption occurred in March and April ___MASK95___ 1977 and lasted for ten days . There was no previous eruption . The magmatic material was olivine basalt from a mantle source . Pyroclastic surge from the eruptions traveled to the northwest . The volume ___MASK95___ lava erupted was 9x105 m3 and the volume ___MASK95___ tephra expelled was 2 . 6x107 m3 . The Quaternary age Gas Rocks dacite domes some three km to the northeast were the site ___MASK95___ a phreatic eruption some 2300 years ago . A diatreme , sometimes known as a maar - diatreme volcano , is a volcanic pipe formed by a gaseous explosion . When magma rises up through a crack in the ___MASK28___ ' s crust and makes contact with a shallow body ___MASK95___ ground water , rapid expansion ___MASK95___ heated water vapor and volcanic gases can cause a series ___MASK95___ explosions . A relatively shallow crater is left ( known as a maar ) and a rock filled fracture ( the actual diatreme ) in the ___MASK28___ ' s crust . Diatremes breach the ___MASK28___ ' s surface and produce a steep inverted cone shape . A mineral is a naturally occurring chemical compound , usually ___MASK95___ crystalline form and abiogenic in origin . A mineral has one specific chemical composition , whereas a rock can be an aggregate ___MASK95___ different minerals or mineraloids . The study ___MASK95___ minerals is called mineralogy . A marginal sea is a division ___MASK95___ an ocean , partially enclosed by islands , archipelagos , or peninsulas , adjacent to or widely open to the open ocean at the surface , and / or bounded by submarine ridges on the sea floor .