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The total amount of water locked up in the mantle has been calculated based on the total area of polygonal ground and an estimated depth of 10 meters. This volume is equal to a layer 2.5 meters deep spread over the entire planet. This compares to a 30-meter depth over the whole planet for the water
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discovered water ice with made direct observations since it landed in a field of polygons. In fact, its landing rockets exposed pure ice. Theory had predicted that ice would be found under a few cm of soil. This mantle layer is called "latitude dependent mantle" because its occurrence is related
324:
Mantle forms when the
Martian climate is different than the present climate. The tilt or obliquity of the axis of the planet changes a great deal. The Earth’s tilt changes little because our rather large moon stabilizes the Earth. Mars only has two very small moons that do not possess enough
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Levy, J., J. Head, D. Marchant, D. Kowalewski. 2008. Identification of sublimation-type thermal contraction crack polygons at the proposed NASA Phoenix landing site: Implications for substrate properties and climate-driven morphological evolution. Geophys. Res. Lett. 35. doi:10.1029/2007GL032813.
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Since the top, polygon layer is fairly smooth although the underlying brain terrain is irregular; it is believed that the mantle layer that contains the polygons needs to be 10–20 meters thick to smooth out the irregularities. The mantle layer lasts for a very long time before all the ice is gone
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51:. Along the outer rim of the crater, the mantle is displayed as layers. This suggests that the mantle was deposited multiple times in the past. Picture was taken with HiRISE under HiWish program. The layers are enlarged in the next image.
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It fell as snow and ice-coated dust. There is good evidence that this mantle is ice-rich. The shapes of the polygons common on many surfaces suggest ice-rich soil. High levels of hydrogen (probably from water) have been found with
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Mitrofanov, I., and 11 colleagues. 2007b. Water ice permafrost on Mars: Layering structure and subsurface distribution according to HEND/Odyssey and MOLA/ MGS data. Geophys. Res. Lett. 34 (18). doi:10.1029/2007GL030030.
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Madeleine, J., F. Forget, J. Head, B. Levrard, F. Montmessin. 2007. Exploring the northern mid-latitude glaciation with a general circulation model. In: Seventh
International Conference on Mars. Abstract 3096.
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57:
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Kuzmin, R, et al. 2004. Regions of potential existence of free water (ice) in the near-surface martian ground: Results from the Mars
Odyssey High-Energy Neutron Detector (HEND). Solar System Research 38 (1),
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because a protective lag deposit forms on the top. The mantle contains ice and dust. After a certain amount of ice disappears from sublimation the dust stays on the top, forming the lag deposit.
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to the latitude. It is this mantle that cracks and then forms polygonal ground. This cracking of ice-rich ground is predicted based on physical processes. Another type of surface is called "
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Much of the
Martian surface is covered with a thick ice-rich, mantle layer that has fallen from the sky a number of times in the past. In some places a number of layers are visible in the mantle.
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Levy, J., et al. 2009. Thermal contraction crack polygons on Mars: Classification, distribution, and climate implications from HiRISE observations. J. Geophys. Res. 114. doi:10.1029/2008JE003273.
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Marchant, D., et al. 2002. Formation of patterned ground and sublimation till over
Miocene glacier ice in Beacon valley, southern Victoria land, Antarctica. Geol. Soc. Am. Bull. 114, 718–730.
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Laskar, J., A. Correia, M. Gastineau, F. Joutel, B. Levrard, and P. Robutel. 2004. Long term evolution and chaotic diffusion of the insolation quantities of Mars. Icarus 170, 343-364.
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Mangold, N., et al. 2004. Spatial relationships between patterned ground and ground ice detected by the neutron spectrometer on Mars. J. Geophys. Res. 109 (E8). doi:10.1029/ 2004JE002235.
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gravity to stabilize its tilt. When the tilt of Mars exceeds around 40 degrees (from today's 25 degrees), ice is deposited in certain latitude bands where much mantle exists today.
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Marchant, D., J. Head. 2007. Antarctic dry valleys: Microclimate zonation, variable geomorphic processes, and implications for assessing climate change on Mars. Icarus 192, 187–222
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Kreslavsky, M., J. Head. 2006. Modification of impact craters in the northern plains of Mars: Implications for the
Amazonian climate history. Meteorit. Planet. Sci. 41, 1633–1646.
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Pollack, J., D. Colburn, F. Flaser, R. Kahn, C. Carson, and D. Pidek. 1979. Properties and effects of dust suspended in the martian atmosphere. J. Geophys. Res. 84, 2929-2945.
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Close up view of mantle, as seen by HiRISE under the HiWish program. Mantle may be composed of ice and dust that fell from the sky during past climatic conditions. Location is
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Feldman, W., et al. 2008. North to south asymmetries in the water-equivalent hydrogen distribution at high latitudes on Mars. J. Geophys. Res. 113. doi:10.1029/2007JE003020.
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Kreslavsky, M., J. Head, J. 2002. Mars: Nature and evolution of young, latitude-dependent water-ice-rich mantle. Geophys. Res. Lett. 29, doi:10.1029/ 2002GL015392.
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Mustard, J., et al. 2001. Evidence for recent climate change on Mars from the identification of youthful near-surface ground ice. Nature 412 (6845), 411–414.
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Mustard, J., et al. 2001. Evidence for recent climate change on Mars from the identification of youthful near-surface ground ice. Nature 412 (6845), 411–414.
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Levy, J. et al. 2010. Thermal contraction crack polygons on Mars: A synthesis from HiRISE, Phoenix, and terrestrial analog studies. Icarus: 206, 229-252.
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Kreslavsky, M.A., Head, J.W., 2002. High-latitude Recent
Surface Mantle on Mars: New Results from MOLA and MOC. European Geophysical Society XXVII, Nice.
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Mellon, M., B. Jakosky. 1995. The distribution and behavior of
Martian ground ice during past and present epochs. J. Geophys. Res. 100, 11781–11799.
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Boynton, W., and 24 colleagues. 2002. Distribution of hydrogen in the nearsurface of Mars: Evidence for sub-surface ice deposits. Science 297, 81–85
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Brain terrain being formed from a thicker layer, as seen by HiRISE under HiWish program. Arrows show the thicker unit breaking up into small cells.
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Close view of mantle, as seen by HiRISE under HiWish program Arrows show craters along edge which highlight the thickness of mantle. Location is
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Mellon, M. 1997. Small-scale polygonal features on Mars: Seasonal thermal contraction cracks in permafrost. J. Geophys. Res. 102, 25,617-625,628.
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Schorghofer, N., O. Aharonson. 2005. Stability and exchange of subsurface ice on Mars. J. Geophys. Res. 110 (E05). doi:10.1029/2004JE002350.
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Head, J.W., Mustard, J.F., Kreslavsky, M.A., Milliken, R.E., Marchant, D.R., 2003. Recent ice ages on Mars. Nature 426 (6968), 797–802.
270:" as it looks like the surface of a human brain. Brain terrain lies under polygonal ground when the two are both visible in a region.
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Close view that displays the thickness of the mantle, as seen by HiRISE under HiWish program
Location is Ismenius Lacus quadrangle.
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Mangold, N. 2005. High latitude patterned grounds on Mars: Classification, distribution and climatic control. Icarus 174, 336–359.
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Feldman, W., and 12 colleagues. 2002. Global distribution of neutrons from Mars: Results from Mars
Odyssey. Science 297, 75–78.
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Mitrofanov, I. et al. 2007a. Burial depth of water ice in Mars permafrost subsurface. In: LPSC 38, Abstract #3108. Houston, TX.
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Head, J., J. Mustard, M. Kreslavsky, R. Milliken, D. Marchant. 2003. Recent ice ages on Mars. Nature 426 (6968), 797–802.
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Mutch, T.A., and 24 colleagues, 1976. The surface of Mars: The view from the Viking2 lander. Science 194 (4271), 1277–1283.
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Close view of places covered and not covered by mantle layer which falls from the sky when climate changes. Location is
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Close view of the edge of mantle, as seen by HiRISE under the HiWish program Location is Hellas quadrangle.
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Washburn, A. 1973. Periglacial Processes and Environments. St. Martin’s Press, New York, pp. 1–2, 100–147.
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Wide view of surface with spots displaying mantle, as seen by HiRISE under HiWish program Location is the
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Enlargement of previous image of mantle layers. Four to five layers are visible. Location is the
32:. Mantle was probably formed from snow and dust falling during a different climate. Location is
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Mutch, T., et al. 1977. The geology of the Viking Lander 2 site. J. Geophys. Res. 82, 4452–4467.
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name= Touma J. and J. Wisdom. 1993. The Chaotic Obliquity of Mars. Science 259, 1294-1297.
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Surface showing appearance with and without mantle covering, as seen by HiRISE, under the
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382:"HiRISE | Layered Mantling Deposits in the Northern Mid-Latitudes (ESP_048897_2125)"
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Schorghofer, N., 2007. Dynamics of ice ages on Mars. Nature 449 (7159), 192–194
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Context picture showing origin of next picture. The location is a region of
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Open and closed-cell brain terrain, as seen by HiRISE, under HiWish program.
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Close view of mantle, as seen by HiRISE under HiWish program Location is
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Schorghofer, N., 2007. Dynamics of ice ages on Mars. Nature 449, 192–194.
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Hecht, M. 2002. Metastability of water on Mars. Icarus 156, 373–386
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HiRISE image showing smooth mantle covering parts of a crater in the
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Mantle layers, as seen by HiRISE under HiWish program. Location is
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Close view of mantle, as seen by HiRISE under HiWish program
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Close view of mantle, as seen by HiRISE under HiWish program
261:. Thermal measurements from orbit suggest ice. The
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Layers in mantle deposit, as seen by HiRISE, under the
118:. Picture taken with HiRISE under HiWish program.
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321:locked up in the north and south polar caps.
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286:. Image from HiRISE under HiWish program.
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87:in Phaethontis quadrangle.
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65:Phaethontis quadrangle
49:Phaethontis quadrangle
284:lineated valley fill
263:Phoenix (spacecraft)
34:Thaumasia quadrangle
132:Cebrenia quadrangle
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101:Eridania quadrangle
222:Arcadia quadrangle
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461:Phoenix
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