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The Elysium quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Elysium quadrangle is also referred to as MC-15 (Mars Chart-15).〔Davies, M.E.; Batson, R.M.; Wu, S.S.C. “Geodesy and Cartography” in Kieffer, H.H.; Jakosky, B.M.; Snyder, C.W.; Matthews, M.S., Eds. ''Mars.'' University of Arizona Press: Tucson, 1992.〕 The Elysium quadrangle covers the area 180° to 225° west longitude and 0° to 30° north latitude on Mars. Elysium Planitia is in the Elysium quadrangle. The Elysium quadrangle includes a part of Lucus Planum. A small part of the Medusae Fossae Formation lies in this quadrangle. The largest craters in this quadrangle are Eddie (crater), Lockyer (crater), and Tombaugh (Martian crater).Elysium contains major volcanoes named Elysium Mons and Albor Tholus and river valleys—one of which, Athabasca Valles may be one of the youngest on Mars. On the east side is an elongated depression called Orcus Patera. A large lake may once have existed in the south near Lethe Valles and Athabasca Valles.〔Cabrol, N. and E. Grin (eds.). 2010. Lakes on Mars. Elsevier. NY.〕 == Volcanoes == The Elysium quadrangle contains the volcanoes Elysium Mons and Albor Tholus. Much of this area is covered with lava flows, some can even be shown approaching, then stopping upon reaching higher ground. (See pictures below for examples) Sometimes when lava flows the top cools quickly into a solid crust. However, the lava below often still flows, this action breaks up the top layer making it very rough.〔(【引用サイトリンク】 title=Southern Margin of Cerberus Palus (PSP_010744_1840) )〕 Such rough flow is called aa. Research, published in January 2010, described the discovery of a vast single lava flow, the size of the state of Oregon, that "was put in place turbulently over the span of several weeks at most."〔http://www.jpl.nasa.gov/news/features.cfm?feature=2438〕 This flow, near Athabasca Valles, is the youngest lava flow on Mars. It is thought to be of Late Amazonian Age.〔Jaeger, W. et al. 2010. Emplacement of the youngest flood lava on Mars: A short, turbulent story. Icarus: 205. 230-243.〕 Other researchers disagree with this idea. Under Martian conditions lava should not stay fluid very long.〔 Image:Elysium map.JPG|Map of Elysium quadrangle. Elysium Mons and Albor Tholus are large volcanoes. Image:Lava flow in Elysium.JPG|Lava flow in Elysium. There are many lava flows in Elysium. In this one, the lava flowed toward the upper right. Image taken by Mars Global Surveyor, under the MOC Public Targeting Program. Image:Lava flows in Elysium.JPG|Lava flows in Elysium as seen by HiRISE. Upper part of image shows lava that solidified on the top then crumpled as lava still moved. Image:Athabasca Cones.jpg|Cones in Athabasca Vallis, as seen by HiRISE. Cones were formed from lava interacting with ice. Larger cones in upper image were produced when water/steam forced its way through thicker layer of lava. Difference between highest elevation (red) to lowest (dark blue) is . 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Elysium quadrangle」の詳細全文を読む スポンサード リンク
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