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Mangala Valles is a complex system of criss-crossing channels on Mars, located in the Tharsis region and in the Memnonia quadrangle. It originating in the Hesperian and Amazonian epochs. It is thought to be an outflow channel, carved by catastrophic floods, and the release of vast quantities of water across the Martian surface. This flooding was probably initiated by tectonic stretching and the formation of a graben, Mangala Fossa, at the channels' head, perhaps breaching a pressurized aquifer trapped beneath a thick "cryosphere" (layer of frozen ground) beneath the surface.〔(【引用サイトリンク】title=Mars Channels and Valleys )〕〔Carr, M. 1979. Formation of martian flood features by release of water from confined aquifers. J. Geophys. Res. 84: 2995-3007.〕〔Hanna, J. and R. Phillips. 2005. Tectonic pressurization of aquifers in the formation of Mangala and Athabasca Valles on Mars. LPSC XXXVI. Abstract 2261.〕 Mangala Valles contains several basins which filled, then the overflow went through a series of spillways.〔Cabrol, N. and E. Grin (eds.). 2010. Lakes on Mars. Elsevier. NY.〕〔Emrick, C. and R. De Hon. 1999. Flood discharge through Labou Vallis, Mars. Lunar Planet. Sci. Conf. XXX: Abstract #1893.〕 One source of waters for the system was Memonia Fossae, but water also probably came from a large basin centered at 40 degrees S.〔Zimbelman, J. et al. 1992. Volatile history of Mangala Valles, Mars. J. Geophys. Res. 97: 18309-18317〕〔De Hon, R. 1994. Lacustrine sedimentation in lower Mangals Valles. Mars Lunar Planet. Sci. Conf. XXVII: 295-296〕 A recent study that used photogeologic analysis, geomorphic surface mapping, cratering statistics, and relative stratigraphy, demonstrated that Mangala Valles was flooded by water at least twice and covered with lava at least three times during the Late Amazonian. The presence of scoured bedrock at the base of the mapped stratigraphy, together with evidence from crater retention ages, suggests that fluvial activity came before lava flows. These alternating periods of aqueous flooding and volcanism are similar to that of other outflow systems on Mars, such as Kasei Valles, and Ravi Vallis.〔Keskea, A., C. Hamilton, A. McEwen, I. Daubar. Episodes of fluvial and volcanic activity in Mangala Valles, Mars. Icarus:245, 333-347.〕 There are many wind-sculpted ridges or yardangs covering many of the surfaces in the Mangala Valles region.〔(【引用サイトリンク】title=Catalog Page for PIA03827 )〕〔(【引用サイトリンク】title=The Planet Mars: A History of Observation and Discovery )〕 "Mangala" comes from the word for Mars in Sanskrit. ==In fiction== * Mangala Valles is referred to in Michael Crichton's book ''Sphere''. * In Stephen Baxter's novel ''Voyage'', it is the location of the first manned Mars landing. * It is also the location of the first manned Mars base in 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「Mangala Valles」の詳細全文を読む スポンサード リンク
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