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The Cerberus Fossae are a series of semi-parallel fissures on Mars formed by faults which pulled the crust apart in the Cerberus region. It is 1235 km across and centered at 11.28 °N and 166.37 °W. It's Northernmost Latitude is 16.16 °N and Southernmost Latitude 6.23 °N. Easternmost and Westernmost Longitudes are 174.72 °E and 154.43 °E respectively. 〔http://planetarynames.wr.usgs.gov/Feature/1109;jsessionid=A00BEFDA78AB1F2F7E97F064A5D7AC11〕 Ripples seen at the bottom of the fault are sand blown by the wind. The underlying cause for the faulting was magma pressure related to the formation of the Elysium volcanic field, located to the northwest. The faults pass through pre-existing features such as hills, indicating that it is a younger feature. The formation of the fossae is suspected to have released pressurized underground water, previously confined by the cryosphere, with flow rates up to 2 × 106 m3s−1, leading to the creation of the Athabasca Valles.〔Cabrol, N. and E. Grin (eds.). 2010. Lakes on Mars. Elsevier. NY〕〔Burr, D. et al. 2002. Repeated aqueous flooding from the Cerberus Fossae: evidence for very recently extant deep groundwater on Mars. Icarus. 159: 53-73.〕 Marte Vallis is another channel that was formed from water released from Cerberus Fossae.〔Gareth, A. B. Campbell, L. Carter, J. Plaut, R. Phillips. 2013. 3D Reconstruction of the Source and Scale of Buried Young Flood Channels on Mars. Science, March 7, DOI:10.1126/Science.1234787〕 A 2005 photo of a locale within Elysium Planitia at 5° N, 150° E by the Mars Express spacecraft shows what may be ash-covered water ice. The volume of ice is estimated to be by in size and deep, similar in size and depth to the North Sea. The ice is thought to be the remains of water floods from the Cerberus Fossae fissures about 2 to 10 million years ago. The surface of the area is broken into 'plates' like broken ice floating on a lake. Impact crater counts show that the plates are up to 1 million years older than the gap material, showing that the area solidified much too slowly for the material to be basaltic lava. However, early radar analysis suggests there's no evidence of 'pack ice' tens of meters thick as hypothesized based on the images from Mars Express of the area. This is in support of the US view of images of the area, based on impact crater morphology which do not show any evidences of meteorite hitting anything but solid stone lava fields〔(1866.PDF )〕 Other researchers have found evidence of past ice in the area; they believe that lava flows may not have been involved.〔Cabrol, N. and E. Grin (eds.). 2010. Lakes on Mars. Elsevier. NY〕 Image:Cerberus Fossae from Themis.JPG|Cerberus Fossae, as seen from THEMIS. Image:Cerberus Fossae dark emission.JPG|Cerberus Fossae dark emission of dark material, as seen by HiRISE. Narrow band of material is coming out of the trough. Scale bar is 500 meters long. Image:Cerberus Fossae with HiRISE.JPG|Cerberus Fossae, as seen by HiRISE. Image:Angular_Unconformity_in_Cerberus.JPG|Angular Unconformity in Cerberus Fossae, as seen by HiRISE. Click on image to see the angles of the layers. Image:Troughs showing blue in Elysium Planitia.JPG|Portion of a trough (fossa) in Elysium, as seen by HiRISE under the HiWish program. Blue indicates probably seasonal frost. == See also == *Geology of Mars * Lakes on Mars 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「Cerberus Fossae」の詳細全文を読む スポンサード リンク
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