Polygonal patterned ground

Last updated

Polygonal, patterned ground is quite common in some regions of Mars. [1] [2] [3] [4] [5] [6] [7] It is commonly believed to be caused by the sublimation of ice from the ground. Sublimation is the direct change of solid ice to a gas. This is similar to what happens to dry ice on the Earth. Places on Mars that display polygonal ground may indicate where future colonists can find water ice. Low center polygons have been proposed as a marker for ground ice. [8] Polygonal terrain is also found on earth's permafrost.

Contents

Patterned ground forms in a mantle layer, called latitude dependent mantle, that fell from the sky when the climate was different. [9] [10] [11] [12]

On Mars, researches have found patterned ground that formed from fractures and patterned ground formed by the arrangement of boulders. It is not yet clear what caused boulders to form patterns, but it does not seem that fractures caused the boulders to move around. [13]

Physics

A similar process occurs on Nile crocodiles. Their snout skins crack during embryo development, forming polygonal patterns. Crocodylus niloticus im Kolner Zoo -20140321-RM-104020.jpg
A similar process occurs on Nile crocodiles. Their snout skins crack during embryo development, forming polygonal patterns.

Unlike mudcracks, which are dominated by T-junctions, polygonal terrain is dominated by Y-junctions. It is formed by repeatedly annealing the crack pattern, as the same ground is partially melted every summer, then frozen every winter, until thousands of years later, it settles into a thermodynamically favored state, which is dominated by Y-junctions. This is similar to columnar jointing. [14]

Polygons in Mare Australe quadrangle

Polygons in Casius quadrangle

Polygons in Hellas quadrangle

Sizes and formation of polygonal ground

Fractured polygonal ground is generally divided into two kinds: high center and low center. The middle of a high center polygon is 10 meters across and its troughs are 2–3 meters wide. Low center polygons are 5–10 meters across and the boundary ridges are 3–4 meters wide. [15] [16] [17]

High center polygons are higher in the center and lower along their boundaries. It forms from increased sublimation around cracks in a surface. Cracks are common in ice-rich surfaces. [18] [19] [20] [21] [22] [5] [23]

The cracks provide a place of increased surface area for sublimation. After a time the narrow cracks widen to become troughs.

Low center polygons are thought to develop from the high center polygons. The troughs along the edges of high center polygons may become filled with sediment. This thick sediment will retard sublimation, so more sublimation will take place in the center that is protected by a thinner lag deposit. In time, the middle becomes lower than the outer parts. The sediments from the troughs will turn into ridges. [15]

High-center polygons in Noachis quadrangle

High-center polygons in Ismenius Lacus quadrangle

Clastic patterned ground

Many areas of patterned ground were formed by boulders. For, as yet unknown reasons, boulders are often arranged in various shapes that include polygons. A study around Lomonosov Crater found that they were not caused by fracture networks. [13] Clastic patterned ground has been found across the Northern Plains. [24] [25] [26] [27] Another site was Elysium Planitia. [28] Researchers also found this terrain in the Argyre Basin (Argyre quadrangle). [29] [30]

Latitude dependent mantle

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. It fell as snow and ice-coated dust. This mantle layer is called "latitude dependent mantle" because its occurrence is related to the latitude. It is this mantle that cracks and then forms polygonal ground.

The mantle layer lasts for a very long time before all the ice is gone because a protective lag deposit forms on the top. [31] 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. [32] [33] [34]

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. [35] [36] [37] 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 gravity to stabilize its tilt. When the tilt of Mars exceeds around 40 degrees (from today's 25 degrees), ice is deposited in certain bands where much mantle exists today. [38] [39]

Other surface features

Another type of surface is called "brain terrain" 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. [15]

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 is 10–20 meters thick. [40]

"Basketball terrain" is another expression of the surface of Mars. At certain distances it looks like a basketball’s surface. Close-up pictures have revealed it to consist of piles of rocks. [41] [42] [43] [44] Many ideas have been advanced to explain how these piles of rocks are formed. [45] [46]

Many steep surfaces in latitude bands near 40 degrees North and South contain gullies. Some of the gullies show polygons. These have been called "gullygons." [40]

Complex polygonal patterned ground

On the Earth

On the Earth, polygonal, patterned ground is present in ice-rich ground, especially in polar regions.

See also

Related Research Articles

<span class="mw-page-title-main">Utopia Planitia</span> Impact basin on Mars

Utopia Planitia is a large plain within Utopia, the largest recognized impact basin on Mars and in the Solar System with an estimated diameter of 3,300 km (2,100 mi). It is the Martian region where the Viking 2 lander touched down and began exploring on September 3, 1976, and the Zhurong rover touched down on May 14, 2021, as a part of the Tianwen-1 mission. It is located at the antipode of Argyre Planitia, centered at 46.7°N 117.5°E. It is also in the Casius quadrangle, Amenthes quadrangle, and the Cebrenia quadrangle of Mars.

<span class="mw-page-title-main">Terra Sabaea</span> Terra on Mars

Terra Sabaea is a large area on Mars. Its coordinates are 2°N42°E and it covers 4,700 kilometres (2,900 mi) at its broadest extent. It was named in 1979 after a classic albedo feature on the planet. Terra Sabaea is fairly large and parts of it are found in five quadrangles: Arabia quadrangle, Syrtis Major quadrangle, Iapygia quadrangle, Ismenius Lacus quadrangle, and Sinus Sabaeus quadrangle.

<span class="mw-page-title-main">Deuteronilus Mensae</span> Mensae on Mars

Deuteronilus Mensae is a region on Mars 937 km across and centered at 43.9°N 337.4°W. It covers 344°–325° West and 40°–48° North. Deuteronilus region lies just to the north of Arabia Terra and is included in the Ismenius Lacus quadrangle. It is along the dichotomy boundary, that is between the old, heavily cratered southern highlands and the low plains of the northern hemisphere. The region contains flat-topped knobby terrain that may have been formed by glaciers at some time in the past. Deuteronilus Mensae is to the immediate west of Protonilus Mensae and Ismeniae Fossae. Glaciers persist in the region in modern times, with at least one glacier estimated to have formed as recently as 100,000 to 10,000 years ago. Recent evidence from the radar on the Mars Reconnaissance Orbiter has shown that parts of Deuteronilus Mensae do indeed contain ice.

<span class="mw-page-title-main">Ismenius Lacus quadrangle</span> Map of Mars

The Ismenius Lacus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the northwestern portion of Mars' eastern hemisphere and covers 0° to 60° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Ismenius Lacus quadrangle is also referred to as MC-5. The southern and northern borders of the Ismenius Lacus quadrangle are approximately 3,065 km (1,905 mi) and 1,500 km (930 mi) wide, respectively. The north-to-south distance is about 2,050 km (1,270 mi). The quadrangle covers an approximate area of 4.9 million square km, or a little over 3% of Mars' surface area. The Ismenius Lacus quadrangle contains parts of Acidalia Planitia, Arabia Terra, Vastitas Borealis, and Terra Sabaea.

<span class="mw-page-title-main">Casius quadrangle</span> Map of Mars

The Casius quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the north-central portion of Mars' eastern hemisphere and covers 60° to 120° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Casius quadrangle is also referred to as MC-6. Casius quadrangle contains part of Utopia Planitia and a small part of Terra Sabaea. The southern and northern borders of the Casius quadrangle are approximately 3,065 km and 1,500 km wide, respectively. The north to south distance is about 2,050 km. The quadrangle covers an approximate area of 4.9 million square km, or a little over 3% of Mars' surface area.

<span class="mw-page-title-main">Diacria quadrangle</span> Map of Mars

The Diacria quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the northwestern portion of Mars' western hemisphere and covers 180° to 240° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Diacria quadrangle is also referred to as MC-2. The Diacria quadrangle covers parts of Arcadia Planitia and Amazonis Planitia.

<span class="mw-page-title-main">Arcadia quadrangle</span> Map of Mars

The Arcadia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the north-central portion of Mars’ western hemisphere and covers 240° to 300° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Arcadia quadrangle is also referred to as MC-3. The name comes from a mountainous region in southern Greece. It was adopted by IAU, in 1958.

<span class="mw-page-title-main">Mare Acidalium quadrangle</span> Map of Mars

The Mare Acidalium quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the northeastern portion of Mars' western hemisphere and covers 300° to 360° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Mare Acidalium quadrangle is also referred to as MC-4.

<span class="mw-page-title-main">Hellas quadrangle</span> Map of Mars

The Hellas quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Hellas quadrangle is also referred to as MC-28 . The Hellas quadrangle covers the area from 240° to 300° west longitude and 30° to 65° south latitude on the planet Mars. Within the Hellas quadrangle lies the classic features Hellas Planitia and Promethei Terra. Many interesting and mysterious features have been discovered in the Hellas quadrangle, including the giant river valleys Dao Vallis, Niger Vallis, Harmakhis, and Reull Vallis—all of which may have contributed water to a lake in the Hellas basin in the distant past. Many places in the Hellas quadrangle show signs of ice in the ground, especially places with glacier-like flow features.

<span class="mw-page-title-main">Phaethontis quadrangle</span> Map of Mars

The Phaethontis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Phaethontis quadrangle is also referred to as MC-24.

In planetary geology, a pedestal crater is a crater with its ejecta sitting above the surrounding terrain and thereby forming a raised platform. They form when an impact crater ejects material which forms an erosion-resistant layer, thus causing the immediate area to erode more slowly than the rest of the region. Some pedestals have been accurately measured to be hundreds of meters above the surrounding area. This means that hundreds of meters of material were eroded away. The result is that both the crater and its ejecta blanket stand above the surroundings. Pedestal craters were first observed during the Mariner missions.

Scalloped topography is common in the mid-latitudes of Mars, between 45° and 60° north and south. It is particularly prominent in the region of Utopia Planitia, in the northern hemisphere, and in the region of Peneus and Amphitrites Paterae in the southern hemisphere. Such topography consists of shallow, rimless depressions with scalloped edges, commonly referred to as "scalloped depressions" or simply "scallops". Scalloped depressions can be isolated or clustered and sometimes seem to coalesce. A typical scalloped depression displays a gentle equator-facing slope and a steeper pole-facing scarp. This topographic asymmetry is probably due to differences in insolation. Scalloped depressions are believed to form from the removal of subsurface material, possibly interstitial ice, by sublimation. This process may still be happening at present. This topography may be of great importance for future colonization of Mars because it may point to deposits of pure ice.

<span class="mw-page-title-main">Lineated valley fill</span> Martian geologic feature

Lineated valley fill (LVF), also called lineated floor deposit, is a feature of the floors of some channels on Mars, exhibiting ridges and grooves that seem to flow around obstacles. Shadow measurements show that at least some of the ridges are several metres high. LVF is believed to be ice-rich. Hundreds of metres of ice probably lie protected in LVF under a thin layer of debris. The debris consists of wind-borne dust, material from alcove walls, and lag material remaining after ice sublimated from a rock-ice mixture. Some glaciers on Earth show similar ridges. High-resolution pictures taken with HiRISE reveal that some of the surfaces of lineated valley fill are covered with strange patterns called closed-cell and open-cell brain terrain. The terrain resembles a human brain. It is believed to be caused by cracks in the surface accumulating dust and other debris, together with ice sublimating from some of the surfaces. The cracks are the result stress from gravity and seasonal heating and cooling. This same type of surface is present on Lobate debris aprons and Concentric crater fill so all three are believed to be related.

<span class="mw-page-title-main">Protonilus Mensae</span> Martian plain

Protonilus Mensae is an area of Mars in the Ismenius Lacus quadrangle. It is centered on the coordinates of 43.86° N and 49.4° E. Its western and eastern longitudes are 37° E and 59.7° E. North and south latitudes are 47.06° N and 39.87° N. Protonilus Mensae is between Deuteronilus Mensae and Nilosyrtis Mensae; all lie along the Martian dichotomy boundary. Its name was adapted by the IAU in 1973.

HiWish is a program created by NASA so that anyone can suggest a place for the HiRISE camera on the Mars Reconnaissance Orbiter to photograph. It was started in January 2010. In the first few months of the program 3000 people signed up to use HiRISE. The first images were released in April 2010. Over 12,000 suggestions were made by the public; suggestions were made for targets in each of the 30 quadrangles of Mars. Selected images released were used for three talks at the 16th Annual International Mars Society Convention. Below are some of the over 4,224 images that have been released from the HiWish program as of March 2016.

<span class="mw-page-title-main">Gullies on Mars</span> Incised networks of narrow channels and sediments on Mars

Martian gullies are small, incised networks of narrow channels and their associated downslope sediment deposits, found on the planet of Mars. They are named for their resemblance to terrestrial gullies. First discovered on images from Mars Global Surveyor, they occur on steep slopes, especially on the walls of craters. Usually, each gully has a dendritic alcove at its head, a fan-shaped apron at its base, and a single thread of incised channel linking the two, giving the whole gully an hourglass shape. They are estimated to be relatively young because they have few, if any craters. A subclass of gullies is also found cut into the faces of sand dunes, that are themselves considered to be quite young. Linear dune gullies are now considered recurrent seasonal features.

<span class="mw-page-title-main">Glaciers on Mars</span> Extraterrestrial bodies of ice

Glaciers, loosely defined as patches of currently or recently flowing ice, are thought to be present across large but restricted areas of the modern Martian surface, and are inferred to have been more widely distributed at times in the past. Lobate convex features on the surface known as viscous flow features and lobate debris aprons, which show the characteristics of non-Newtonian flow, are now almost unanimously regarded as true glaciers.

Chaos terrain on Mars is distinctive; nothing on Earth compares to it. Chaos terrain generally consists of irregular groups of large blocks, some tens of kilometers across and a hundred or more meters high. The tilted and flat topped blocks form depressions hundreds of metres deep. A chaotic region can be recognized by a rat's nest of mesas, buttes, and hills, chopped through with valleys which in places look almost patterned. Some parts of this chaotic area have not collapsed completely—they are still formed into large mesas, so they may still contain water ice. Chaos regions formed long ago. By counting craters and by studying the valleys' relations with other geological features, scientists have concluded the channels formed 2.0 to 3.8 billion years ago.

The common surface features of Mars include dark slope streaks, dust devil tracks, sand dunes, Medusae Fossae Formation, fretted terrain, layers, gullies, glaciers, scalloped topography, chaos terrain, possible ancient rivers, pedestal craters, brain terrain, and ring mold craters.

<span class="mw-page-title-main">Latitude dependent mantle</span>

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.

References

  1. ↑ http://www.diss.fu-berlin.de/diss/servlets/MCRFileNodeSe%5B%5D rvlet/FUDISS_derivate_000000003198/16_ColdClimateLandforms-13-utopia.pdf?hosts=
  2. ↑ Kostama, V.-P.; Kreslavsky, Head (2006). "Recent high-latitude icy mantle in the northern plains of Mars: Characteristics and ages of emplacement". Geophys. Res. Lett. 33 (11): L11201. Bibcode:2006GeoRL..3311201K. CiteSeerX   10.1.1.553.1127 . doi:10.1029/2006GL025946. S2CID   17229252.
  3. ↑ Malin, M.; Edgett, K. (2001). "Mars Global Surveyor Mars Orbiter Camera: Interplanetary cruise through primary mission". J. Geophys. Res. 106 (E10): 23429–23540. Bibcode:2001JGR...10623429M. doi: 10.1029/2000je001455 .
  4. ↑ Milliken, R.; et al. (2003). "Viscous flow features on the surface of Mars: Observations from high-resolution Mars Orbiter Camera (MOC) images". J. Geophys. Res. 108 (E6): E6. Bibcode:2003JGRE..108.5057M. CiteSeerX   10.1.1.506.7847 . doi:10.1029/2002JE002005.
  5. 1 2 Mangold, N (2005). "High latitude patterned grounds on Mars: Classification, distribution and climatic control". Icarus. 174 (2): 336–359. Bibcode:2005Icar..174..336M. doi:10.1016/j.icarus.2004.07.030.
  6. ↑ Kreslavsky, M.; Head, J. (2000). "Kilometer-scale roughness on Mars: Results from MOLA data analysis". J. Geophys. Res. 105 (E11): 26695–26712. Bibcode:2000JGR...10526695K. doi: 10.1029/2000je001259 .
  7. ↑ Seibert, N.; Kargel, J. (2001). "Small-scale martian polygonal terrain: Implications for liquid surface water". Geophys. Res. Lett. 28 (5): 899–902. Bibcode:2001GeoRL..28..899S. doi:10.1029/2000gl012093.
  8. ↑ Soare, R., et al. 2018. POSSIBLE ICE-WEDGE POLYGONISATION IN UTOPIA PLANITIA, MARS, AND ITS POLEWARD LATITUDINAL-GRADIENT. 49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083). 1084.pdf
  9. ↑ Hecht, M (2002). "Metastability of water on Mars". Icarus. 156 (2): 373–386. Bibcode:2002Icar..156..373H. doi:10.1006/icar.2001.6794.
  10. ↑ 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. Bibcode:2001Natur.412..411M. doi:10.1038/35086515. PMID   11473309. S2CID   4409161.
  11. ↑ 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.
  12. ↑ 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. Bibcode:2003Natur.426..797H. doi:10.1038/nature02114. PMID   14685228. S2CID   2355534.
  13. 1 2 Barrett, A.; et al. (2017). "Clastic patterned ground in Lomonosov crater, Mars: examining fracture controlled formation mechanisms". Icarus. 295: 125–139. Bibcode:2017Icar..295..125B. doi: 10.1016/j.icarus.2017.06.008 . hdl: 1893/26993 .
  14. 1 2 Goehring, Lucas; Morris, Stephen W. (2014-11-01). "Cracking mud, freezing dirt, and breaking rocks". Physics Today. 67 (11): 39–44. doi:10.1063/PT.3.2584. ISSN   0031-9228.
  15. 1 2 3 Levy, J.; Head, J.; Marchant, D. (2009). "Concentric crater fill in Utopia Planitia: History and interaction between glacial "brain terrain" and periglacial mantle processes". Icarus. 202 (2): 462–476. Bibcode:2009Icar..202..462L. doi:10.1016/j.icarus.2009.02.018.
  16. ↑ "HiRISE | Hexagons in Icy Terrain (PSP_008883_2245)".
  17. ↑ https://static.uahirise.org/images/2018/details/cut/PSP_008883_2245.jpg [ bare URL image file ]
  18. ↑ Mutch, T.A.; et al. (1976). "The surface of Mars: The view from the Viking2 lander". Science. 194 (4271): 1277–1283. Bibcode:1976Sci...194.1277M. doi:10.1126/science.194.4271.1277. PMID   17797083. S2CID   38178368.
  19. ↑ Mutch, T.; et al. (1977). "The geology of the Viking Lander 2 site". J. Geophys. Res. 82 (B28): 4452–4467. Bibcode:1977JGR....82.4452M. doi:10.1029/js082i028p04452.
  20. ↑ Levy, J.; et al. (2009). "Thermal contraction crack polygons on Mars: Classification, distribution, and climate implications from HiRISE observations". J. Geophys. Res. 114 (E1): E01007. Bibcode:2009JGRE..114.1007L. doi: 10.1029/2008JE003273 .
  21. ↑ Washburn, A. 1973. Periglacial Processes and Environments. St. Martin’s Press, New York, pp. 1–2, 100–147.
  22. ↑ Mellon, M (1997). "Small-scale polygonal features on Mars: Seasonal thermal contraction cracks in permafrost". J. Geophys. Res. 102 (E11): 25617–625. Bibcode:1997JGR...10225617M. doi: 10.1029/97je02582 .
  23. ↑ Marchant, D.; Head, J. (2007). "Antarctic dry valleys: Microclimate zonation, variable geomorphic processes, and implications for assessing climate change on Mars". Icarus (Submitted manuscript). 192 (1): 187–222. Bibcode:2007Icar..192..187M. doi:10.1016/j.icarus.2007.06.018.
  24. ↑ Balme, M.; et al. (2013). "Morphological evidence for geologically young thaw of ice on Mars: a review of recent studies using high-resolution imaging data" (PDF). Prog. Phys. Geogr. (Submitted manuscript). 37 (3): 289–324. doi:10.1177/0309133313477123. S2CID   129919923.
  25. ↑ Gallangher, M.; et al. (2011). "Sorted clastic stripes, lobes and associated gullies in high-latitude craters on Mars: landforms indicative of very recent, polycyclic ground-ice thaw and liquid flows". Icarus. 211 (1): 458–471. Bibcode:2011Icar..211..458G. doi:10.1016/j.icarus.2010.09.010.
  26. ↑ Johnsson, D.; et al. (2012). "Periglacial mass-wasting landforms on Mars suggestive of transient liquid water in the recent past : insights from solifluction lobes on Svalbard" (PDF). Icarus. 218 (1): 489–505. Bibcode:2012Icar..218..489J. doi:10.1016/j.icarus.2011.12.021.
  27. ↑ Orloff, M.; et al. (2011). "Boulder movement at high northern latitudes of Mars". J. Geophys. Res. 116 (E11): 1–12. Bibcode:2011JGRE..11611006O. doi:10.1029/2011je003811.
  28. ↑ Balme, M.; et al. (2009). "Sorted stone circles in Elysium Planitia, Mars: Implications for recent Martian climate". Icarus. 200 (1): 30–38. Bibcode:2009Icar..200...30B. doi:10.1016/j.icarus.2008.11.010.
  29. ↑ Banks, M.; et al. (2008). "High resolution imaging science experiment (HiRISE) observations of glacial and periglacial morphologies in the circum-Argyre Planitia highlands. Mars". J. Geophys. Res. 113 (E12): E12015. Bibcode:2008JGRE..11312015B. doi:10.1029/2007je002994.
  30. ↑ Soare, R.; et al. (2016). "Sorted (clastic) polygons in the Argyre region, Mars, and possible evidence of pre-and post- glacial periglaciation in the Late Amazonian Epoch". Icarus. 264: 184–197. Bibcode:2016Icar..264..184S. doi:10.1016/j.icarus.2015.09.019.
  31. ↑ Marchant, D.; et al. (2002). "Formation of patterned ground and sublimation till over Miocene glacier ice in Beacon valley, southern Victoria land". Geological Society of America Bulletin. 114 (6): 718–730. Bibcode:2002GSAB..114..718M. doi:10.1130/0016-7606(2002)114<0718:fopgas>2.0.co;2.
  32. ↑ Schorghofer, N.; Aharonson, O. (2005). "Stability and exchange of subsurface ice on Mars" (PDF). J. Geophys. Res. 110 (E5): E05. Bibcode:2005JGRE..110.5003S. doi: 10.1029/2004JE002350 .
  33. ↑ Schorghofer, N (2007). "Dynamics of ice ages on Mars". Nature. 449 (7159): 192–194. Bibcode:2007Natur.449..192S. doi:10.1038/nature06082. PMID   17851518. S2CID   4415456.
  34. ↑ Head, J.; Mustard, J.; Kreslavsky, M.; Milliken, R.; Marchant, D. (2003). "Recent ice ages on Mars". Nature. 426 (6968): 797–802. Bibcode:2003Natur.426..797H. doi:10.1038/nature02114. PMID   14685228. S2CID   2355534.
  35. ↑ name; Touma, J.; Wisdom, J. (1993). "The Chaotic Obliquity of Mars". Science. 259 (5099): 1294–1297. Bibcode:1993Sci...259.1294T. doi:10.1126/science.259.5099.1294. PMID   17732249. S2CID   42933021.
  36. ↑ Laskar, J.; Correia, A.; Gastineau, M.; Joutel, F.; Levrard, B.; Robutel, P. (2004). "Long term evolution and chaotic diffusion of the insolation quantities of Mars" (PDF). Icarus (Submitted manuscript). 170 (2): 343–364. Bibcode:2004Icar..170..343L. doi:10.1016/j.icarus.2004.04.005. S2CID   33657806.
  37. ↑ Levy, J.; Head, J.; Marchant, D.; Kowalewski, D. (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 (4): L04202. Bibcode:2008GeoRL..35.4202L. doi:10.1029/2007GL032813.
  38. ↑ Kreslavsky, M.J.; Head, J. (2002). "Mars: Nature and evolution of young, latitude-dependent water-ice-rich mantle". Geophys. Res. Lett. 29 (15): 14–1–14–4. Bibcode:2002GeoRL..29.1719K. doi: 10.1029/2002GL015392 .
  39. ↑ Kreslavsky, M.; Head, J. (2006). "Modification of impact craters in the northern plains of Mars: Implications for the Amazonian climate history". Meteorit. Planet. Sci. 41 (10): 1633–1646. Bibcode:2006M&PS...41.1633K. doi: 10.1111/j.1945-5100.2006.tb00441.x .
  40. 1 2 Levy, J.; et al. (2010). "Thermal contraction crack polygons on Mars: A synthesis from HiRISE, Phoenix, and terrestrial analog studies". Icarus. 206 (1): 229–252. Bibcode:2010Icar..206..229L. doi:10.1016/j.icarus.2009.09.005.
  41. ↑ Malin, M; Edgett, K. (2001). "Mars global surveyor Mars orbiter camera: interplanetary cruise through primary mission". J. Geophys. Res. 106 (E10): 23429. Bibcode:2001JGR...10623429M. doi: 10.1029/2000je001455 .
  42. ↑ Mellon, M.; et al. (2008). "Periglacial landforms at the Phoenix landing site and the Northern Plains of Mars". J. Geophys. Res. 113 (E4): 1–15. Bibcode:2008JGRE..113.0A23M. doi:10.1029/2007je003039.
  43. ↑ "HiRISE | Basketball Terrain (ESP_011816_2300)".
  44. ↑ "HiRISE | Basketball Terrain (PSP_007254_2320)".
  45. ↑ Kreslavsky, M. A. (2002). "Mars: Nature and evolution of young latitude-dependent water-ice-rich mantle". Geophysical Research Letters. 29 (15): 14–1–14–4. Bibcode:2002GeoRL..29.1719K. doi: 10.1029/2002GL015392 .
  46. ↑ Kreslavsky, M. J. Head (2002). "Mars: Nature and evolution of young latitude-dependent water-ice-rich mantle". Geophysical Research Letters. 29 (15): 14–1–14–4. Bibcode:2002GeoRL..29.1719K. doi: 10.1029/2002gl015392 .
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.