Amenthes quadrangle

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Amenthes quadrangle
USGS-Mars-MC-14-AmenthesRegion-mola.png
Map of Amenthes quadrangle from Mars Orbiter Laser Altimeter (MOLA) data. The highest elevations are red and the lowest are blue.
Coordinates 15°00′N 247°30′W / 15°N 247.5°W / 15; -247.5Coordinates: 15°00′N 247°30′W / 15°N 247.5°W / 15; -247.5
Image of the Amenthes Quadrangle (MC-14). The southern part includes heavily cratered highlands; the northern part contains Elysium Planitia; and, the eastern half includes Isidis basin.

The Amenthes quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Amenthes quadrangle is also referred to as MC-14 (Mars Chart-14).[1] The quadrangle covers the area from 225° to 270° west longitude and from 0° to 30° north latitude on Mars.

This quadrangle contains the Isidis basin, a location where magnesium carbonate was found by MRO. This mineral indicates that water was present and that it was not acidic. There are Dark slope streaks, troughs (fossae), and river valleys (Vallis) in this quadrangle.

Craters[edit]

Some craters in the Amenthes region (as well as other parts of Mars) show ejecta around them that have lobes. It is believed that the lobed shape is caused by an impact into water or ice logged ground. Calculations suggest that ice is stable beneath the Martian surface.

At the equator the stable layer of ice might lie under as much as 1 kilometer of material, but at higher latitudes the ice may be just a few centimeters below the surface. This was proven when the landing rockets on the Phoenix lander blew away surface dust to reveal an ice surface. [2][3] The larger an impact crater, the deeper its penetration, a large crater is more likely to have a lobate ejecta since it went down to the ice layer. When even small craters have lobes, the ice level is close to the surface. [4] This idea would be very important for future colonists on Mars who would like to live near a source of water.

Impact craters generally have a rim with ejecta around them, in contrast volcanic craters usually do not have a rim or ejecta deposits. [5] Sometimes craters will display layers. Since the collision that produces a crater is like a powerful explosion, rocks from deep underground are tossed unto the surface. Hence, craters can show us what lies deep under the surface.

Hebrus Valles[edit]

Hebrus Vales has tributaries, terraces, and teardrop shaped islands. The tear drop shape of the islands indicate what direction the water used to flow. The terraces may be caused by different layers of rocks or from the water being at different levels.[6] These features are common for the rivers of the Earth.

Gallery[edit]

See also[edit]

References[edit]

  1. ^ 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.
  2. ^ http://www.nasa.gov/mission_pages/phoenix/news/phoenix-20080531.html
  3. ^ http://www.nasa.gov/centers/ames/news/releases/2008/08_108AR_prt.html
  4. ^ http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=31026
  5. ^ Hugh H. Kieffer (1992). Mars. University of Arizona Press. ISBN 978-0-8165-1257-7. Retrieved 7 March 2011. 
  6. ^ http://themis.asu.edu/zoom-20020603a
Mars Quad Map
About this image
MC-14
Amenthes