Memnonia quadrangle

Memnonia quadrangle

Map of Memnonia quadrangle from Mars Orbiter Laser Altimeter (MOLA) data. The highest elevations are red and the lowest are blue.
Coordinates	15°00′S 157°30′W / 15°S 157.5°WCoordinates: 15°00′S 157°30′W / 15°S 157.5°W

Image of the Memnonia Quadrangle (MC-16). The south includes heavily cratered highlands intersected, in the northeastern part, by Mangala Vallis. The north contains undulating wind-eroded deposits and the east contains lava flows from the Tharsis region.

The Memnonia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Memnonia quadrangle is also referred to as MC-16 (Mars Chart-16).^[1]

The quadrangle is a region of Mars that covers latitude -30° to 0° and longitude 135° to 180°.^[2] The western part of Memnonia is a highly cratered highland region that exhibits a large range of crater degradation.

Memnonia includes these topographical regions of Mars:

• Arcadia Planitia
• Amazonis Planitia
• Lucus Planum
• Terra Sirenum
• Daedalia Planum
• Terra Cimmeria

Recently, evidence of water was found in the area. Layered sedimentary rocks were found in the wall and floor of Columbus Crater. These rocks could have been deposited by water or by wind. Hydrated minerals were found in some of the layers, so water may have been involved.^[3]

Many ancient river valleys Vallis including Mangala Vallis, have been found in the Memnonia quadrangle. Mangala appears to have begun with the formation of a graben, a set of faults that may have exposed an aquifer.^[4] Dark slope streaks and troughts (fossae) are present in this quadrangle. Part of the Medusae Fossae Formation is found in the Memnonia quadrangle.

Layers

Columbus Crater contains layers, also called strata. Many places on Mars show rocks arranged in layers. Sometimes the layers are of different colors. Light-toned rocks on Mars have been associated with hydrated minerals like sulfates. The Mars Rover Opportunity examined such layers close-up with several instruments. Some layers are probably made up of fine particles because they seem to break up into find dust. Other layers break up into large boulders so they are probably much harder. Basalt, a volcanic rock, is thought to in the layers that form boulders. Basalt has been identified on Mars in many places. Instruments on orbiting spacecraft have detected clay (also called phyllosilicate) in some layers. Recent research with an orbiting near-infrared spectrometer, which reveals the types of minerals present based on the wavelengths of light they absorb, found evidence of layers of both clay and sulfates in Columbus crater.^[5] This is exactly what would appear if a large lake had slowly evaporated.^[6] Moreover, because some layers contained gypsum, a sulfate which forms in relatively fresh water, life could have formed in the crater.^[7]

Scientists are excited about finding hydrated minerals such as sulfates and clays on Mars because they are usually formed in the presence of water.^[8] Places that contain clays and/or other hydrated minerals would be good places to look for evidence of life.^[9]

Rock can form layers in a variety of ways. Volcanoes, wind, or water can produce layers.^[10]

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  Columbus Crater Layers, as seen by HiRISE. This false-color image is about 800 feet across. Some of the layers contain hydrated minerals such as clay and sulfates.

• 

  Layers in Monument Valley. These are accepted as being formed, at least in part, by water deposition. Since Mars contains similar layers, water remains as a major cause of layering on Mars.

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  Layers in crater wall, as seen by HiRISE under HiWish program

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  Layers exposed at the base of a group of buttes in Mangala Valles in Memnonia quadrangle, as seen by HiRISE under HiWish program. Arrows point to boulders sitting in pits. The pits may have formed by winds, heat from the boulders melting ground ice, or some other process.

Mangala Vallis

Mangala Vallis is a major channel system that contains several basins which filled, then the overflow went through a series of spillways.^[11][12] One source of waters for the system was Memonia Fossae, but water also probably came from a large basin centered at 40 degrees S.^[13][14]

• 

  Mangala Valles, as seen by HiRISE.

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  Mangala Vallis with a streamlined island, as seen by THEMIS.

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  Streamlined feature in Mangala Vallis, as seen by HiRISE under HiWish program. Many dark slope streaks are visible. Location is Memnonia quadrangle.

• 

  Part of Mangala Valles, as seen by HiRISE under HiWish program. Location is Memnonia quadrangle.

Craters

Impact craters generally have a rim with ejecta around them, in contrast volcanic craters usually do not have a rim or ejecta deposits. As craters get larger (greater than 10 km in diameter) they usually have a central peak.^[15] The peak is caused by a rebound of the crater floor following the impact.^[16] 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. At times, bright rays surround craters because the impact has gone down to a bright layer of rocks, then thrown out the bright rocks on the darker surface. An image below from Mars Global Surveyor shows this.

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  Bright rays caused by impact throwing out a bright lower layer. Some bright layers contain hydrated minerals. Picture taken with Mars Global Surveyor, under the MOC Public Targeting Program.

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  Close-up of Columbus Crater, as seen by HiRISE.

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  Nicholson Crater Central Mound, as seen by HiRISE. Click on image to see dark slope streak being diverted by an obstacle.

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  Bernard Crater Floor, as seen by HiRISE. Large cracks are visible on floor.

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  Troughs on the floor of Bernard Crater showing many boulders, as seen by HiRISE under HiWish program

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  Troughs on the floor of Bernard Crater, as seen by HiRISE under HiWish program

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  Dejnev Crater Floor, as seen by HiRISE. Scale bar is 500 meters long. Click on image to see large pits.

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  Erosion of crater deposit in Lucus Planum, as seen by HiRISE under HiWish program.

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  Close-up of layers in a pit on crater floor, as seen by HiRISE under HiWish program.

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  Williams Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter).

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  Middle section of Burton Crater, showing central mound, as seen by CTX camera (on Mars Reconnaissance Orbiter).

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  Central mound of Burton Crater, showing dark slope streaks, as seen by CTX camera (on[Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Burton Crater.

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  East side of Ejriksson Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter).

Yardangs

Yardangs are common in some regions on Mars, especially in what's called the "Medusae Fossae Formation."^[17] They are formed by the action of wind on sand sized particles; hence they often point in the direction that the winds were blowing when they were formed.

,

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  Wide view of yardangs in Lucus Planum, as seen by HiRISE under HiWish program

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  Close view of yardangs in previous image, as seen by HiRISE under HiWish program

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  Close view of yardangs from a previous image, as seen by HiRISE under HiWish program

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  Close up of crater floor showing yardangs and dark slope streaks,as seen by HiRISE under HiWish program

Why are Craters important?

The density of impact craters is used to determine the surface ages of Mars and other solar system bodies.^[18] The older the surface, the more craters present. Crater shapes can reveal the presence of ground ice.

The area around craters may be rich in minerals. On Mars, heat from the impact melts ice in the ground. Water from the melting ice dissolves minerals, and then deposits them in cracks or faults that were produced with the impact. This process, called hydrothermal alteration, is a major way in which ore deposits are produced. The area around Martian craters may be rich in useful ores for the future colonization of Mars.^[19] Studies on the earth have documented that cracks are produced and that secondary minerals veins are deposited in the cracks.^[20][21][22] Images from satellites orbiting Mars have detected cracks near impact craters.^[23] Great amounts of heat are produced during impacts. The area around a large impact may take hundreds of thousands of years to cool.^[24][25][26] Many craters once contained lakes.^[27][28][29] Because some crater floors show deltas, we know that water had to be present for some time. Dozens of deltas have been spotted on Mars.^[30] Deltas form when sediment is washed in from a stream entering a quiet body of water. It takes a bit of time to form a delta, so the presence of a delta is exciting; it means water was there for a time, maybe for many years. Primitive organisms may have developed in such lakes; hence, some craters may be prime targets for the search for evidence of life on the Red Planet.^[31]

Dark slope streaks

Many places on Mars show dark slope streaks on steep slopes like crater walls. It seems that the youngest streaks are dark; they become lighter with age.^[32] Often they begin as a small narrow spot then widen and extend downhill for hundreds of meters. Several ideas have been advanced to explain the streaks. Some involve water.^[33] or even the growth of organisms.^[34][35] The streaks appear in areas covered with dust. Much of the Martian surface is covered with dust. Fine dust settles out of the atmosphere covering everything. We know a lot about this dust because the solar panels of Mars Rovers get covered with dust. The power of the Rovers has been saved many times by the wind, in the form of dust devils, that have cleared the panels and boosted the power. From these observations with the Rovers, we know that the process of dust coming out of the atmosphere then returning happens over and over.^[36]

It is most generally accepted that the streaks represent avalanches of dust.^[37] The streaks appear in areas covered with dust. When a thin layer of dust is removed, the underlying surface is dark. Much of the Martian surface is covered with dust. Dust storms are frequent, especially when the spring season begins in the southern hemisphere. At that time, Mars is 40% closer to the sun. The orbit of Mars is much more elliptical then the Earth's. That is the difference between the farthest point from the sun and the closest point to the sun is very great for Mars, but only slight for the Earth. Also, every few years, the entire planet is engulfed in a global dust storm. When NASA's Mariner 9 craft arrived there, nothing could be seen through the dust storm.^[16][38] Other global dust storms have also been observed, since that time. Dark streaks can be seen in the image below taken with HiRISE of the central mound in Nicholson Crater. At least one streak in the image splits into two when encountering an obstacle.

Research, published in January 2012 in Icarus, found that dark streaks were initiated by airblasts from meteorites traveling at supersonic speeds. The team of scientists was led by Kaylan Burleigh, an undergraduate at the University of Arizona. After counting some 65,000 dark streaks around the impact site of a group of 5 new craters, patterns emerged. The number of streaks was greatest closer to the impact site. So, the impact somehow probably caused the streaks. Also, the distribution of the streaks formed a pattern with two wings extending from the impact site. The curved wings resembled scimitars, curved knives. This pattern suggests that an interaction of airblasts from the group of meteorites shook dust loose enough to start dust avalanches that formed the many dark streaks. At first it was thought that the shaking of the ground from the impact caused the dust avalanches, but if that was the case the dark streaks would have been arranged symmetrically around the impacts, rather than being concentrated into curved shapes.^[39][40]

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  Minio Vallis Hanging Valleys, as seen by HiRISE. Two hanging valleys are visible, as well as many dark slope streaks.

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  Tinia Valles, as seen by HiRISE. Full size image shows dark slope streaks.

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  Labou Vallis, as seen by HiRISE. Ful size image shows old and new (darker) dark slope streaks.

Fossa on Mars

Large troughs (long narrow depressions) are called fossae in the geographical language used for Mars. This term is derived from Latin; therefore fossa is singular and fossae is plural.^[41] Troughs form when the crust is stretched until it breaks. The stretching can be due to the large weight of a nearby volcano. A trough often has two breaks with a middle section moving down, leaving steep cliffs along the sides; such a trough is called a graben.^[42] Lake George, in northern New York State, is a lake that sits in a graben.

Other ideas have been suggested for the formation of fossae. There is evidence that they are associated with dikes of magma. Magma might move along, under the surface, breaking the rock and more importantly melting ice. The resulting action would cause a crack to form at the surface. Dikes caused both by tectonic stretching (extension) and by dikes are found in Iceland.^[43] An example of a graben caused by a dike is shown below in the image Memnonia Fossae, as seen by HiRISE.

It appears that the water started coming out of the surface to form Mangala Vallis when a graben was formed.^[4][44]

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  Graben in Memnonia Fossae, as seen by HiRISE. This graben is believed to be the result of magmatic dikes rather than regional tectonic stretching. The scale bar is 1000 meters long.

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  Sirenum Fossae, as seen by HiRISE. More information can be found at Fossa (geology).

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  Large pits in Sirenum Fossae, as seen by HiRISE under HiWish program

Valles

There is enormous evidence that water once flowed in river valleys on Mars. Images of curved channels have been seen in images from Mars spacecraft dating back to the early seventies with the Mariner 9 orbiter.^{[45][46][47][48]} Vallis (plural valles) is the Latin word for valley. It is used in planetary geology for the naming of landform features on other planets, including what could be old river valleys that were discovered on Mars, when probes were first sent to Mars. The Viking Orbiters caused a revolution in our ideas about water on Mars; huge river valleys were found in many areas. Space craft cameras showed that floods of water broke through dams, carved deep valleys, eroded grooves into bedrock, and traveled thousands of kilometers.^[16][49][50] Some valles on Mars (Mangala Vallis, Athabasca Vallis, Granicus Vallis, and Tinjar Valles) clearly begin at graben. On the other hand, some of the large outflow channels begin in rubble-filled low areas called chaos or chaotic terrain. It has been suggested that massive amounts of water were trapped under pressure beneath a thick cryosphere (layer of frozen ground), then the water was suddenly released, perhaps when the cryosphere was broken by a fault.^[51][52]

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  Asopus Vallis, as seen by HiRISE.

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  Samara Valles, as seen by HiRISE. Scale bar is 500 meters long.

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  Padus Vallis, as seen by THEMIS. Padus Vallis empties into the Medusae Fossae Formation.

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  Close-up of Padus Vallis, as seen by THEMIS.

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  Minio Vallis, as seen by THEMIS. Minio Vallis is a small river channel near the much larger Mangala Vallis.

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  Sabis Vallis, as seen by THEMIS. The small channels are joining to form Sabis Vallis.

Lava flows

Lava is common on Mars, as it is on many other planetary bodies.

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  Lava flow. Lava flow stopped when it encountered the higher ground of a mound. Picture was taken with HiRISE under HiWish program.

More features of Memnonia quadrangle

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  Surface features along a scarp in Medusae Fossae formation, as seen by HiRISE under HiWish program Location is Memnonia quadrangle.

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  Channels inside and outside of a crater, as seen by HiRISE under HiWish program Branched channels are outside the crater (at the top of the image). The channel then goes into crater, making more branches that are probably on a delta-like form.

Other Mars quadrangles

The thirty cartographic quadrangles of Mars, defined by the United States Geological Survey.^[1][2] The quadrangles are numbered with the prefix "MC" for "Mars Chart."^[3] Click on a quadrangle name link and you will be taken to the corresponding article. North is at the top; 0°N 180°W / 0°N 180°W is at the far left on the equator. The map images were taken by the Mars Global Surveyor.

1. ^ Morton, Oliver (2002). Mapping Mars: Science, Imagination, and the Birth of a World. New York: Picador USA. p. 98. ISBN 0-312-24551-3.
2. ^ "Online Atlas of Mars". Ralphaeschliman.com. Retrieved December 16, 2012.
3. ^ "Catalog Page for PIA03467". Photojournal.jpl.nasa.gov. February 16, 2002. Retrieved December 16, 2012.

0°N 180°W / 0°N 180°W

0°N 0°W / 0°N -0°E

90°N 0°W / 90°N -0°E

MC-01

Mare Boreum

MC-02

Diacria

MC-03

Arcadia

MC-04

Mare Acidalium

MC-05

Ismenius Lacus

MC-06

Casius

MC-07

Cebrenia

MC-08

Amazonis

MC-09

Tharsis

MC-10

Lunae Palus

MC-11

Oxia Palus

MC-12

Arabia

MC-13

Syrtis Major

MC-14

Amenthes

MC-15

Elysium

MC-16

Memnonia

MC-17

Phoenicis

MC-18

Coprates

MC-19

Margaritifer

MC-20

Sabaeus

MC-21

Iapygia

MC-22

Tyrrhenum

MC-23

Aeolis

MC-24

Phaethontis

MC-25

Thaumasia

MC-26

Argyre

MC-27

Noachis

MC-28

Hellas

MC-29

Eridania

MC-30

Mare Australe

See also

• Climate of Mars
• Dark slope streaks
• Fossa (geology)
• Geology of Mars
• Groundwater on Mars
• Impact crater
• Lakes on Mars
• List of quadrangles on Mars
• Lucus Planum
• Vallis
• Valley networks (Mars)
• Water on Mars
• Yardang
• Yardangs on Mars

References

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. USGS Astrogeology: Planetary Map Listing
3. "HiRISE | Sedimentary Layers in Columbus Crater (PSP_010281_1510)". Hirise.lpl.arizona.edu. Retrieved 2012-08-04.
4. "Mars Channels and Valleys". Msss.com. Retrieved 2012-08-04.
5. Cabrol, N. and E. Grin (eds.). 2010. Lakes on Mars. Elsevier.NY.
6. Wray, J. et al. 2009. Columbus Crater and other possible plaelakes in Terra Sirenum, Mars. Lunar and Planetary Science Conference. 40: 1896.
7. "Martian "Lake Michigan" Filled Crater, Minerals Hint". News.nationalgeographic.com. 2010-10-28. Retrieved 2012-08-04.
8. "Target Zone: Nilosyrtis? | Mars Odyssey Mission THEMIS". Themis.asu.edu. Retrieved 2012-08-04.
9. "HiRISE | Craters and Valleys in the Elysium Fossae (PSP_004046_2080)". Hirise.lpl.arizona.edu. Retrieved 2012-08-04.
10. "HiRISE | High Resolution Imaging Science Experiment". Hirise.lpl.arizona.edu?psp_008437_1750. Retrieved 2012-08-04.
11. Cabrol, N. and E. Grin (eds.). 2010. Lakes on Mars. Elsevier. NY.
12. Emrick, C. and R. De Hon. 1999. Flood discharge through Labou Vallis, Mars. Lunar Planet. Sci. Conf. XXX: Abstract #1893.
13. Zimbelman, J. et al. 1992. Volatile history of Mangala Valles, Mars. J. Geophys. Res. 97: 18309-18317
14. De Hon, R. 1994. Lacustrine sedimentation in lower Mangals Valles. Mars Lunar Planet. Sci. Conf. XXVII: 295-296
15. "Stones, Wind, and Ice: A Guide to Martian Impact Craters". Lpi.usra.edu. Retrieved 2012-08-04.
16. Hugh H. Kieffer (1992). Mars. University of Arizona Press. ISBN 978-0-8165-1257-7. Retrieved 7 March 2011.
17. SAO/NASA ADS Astronomy Abstract Service: Yardangs on Mars
18. http://www.lpi.usra.edu/publications/slidesets/stones/
19. http://www.indiana.edu/~sierra/papers/2003/Patterson.html.
20. Osinski, G, J. Spray, and P. Lee. 2001. Impact-induced hydrothermal activity within the Haughton impact structure, arctic Canada: Generation of a transient, warm, wet oasis. Meteoritics & Planetary Science: 36. 731-745
21. http://www.ingentaconnect.com/content/arizona/maps/2005/00000040/00000012/art00007
22. Pirajno, F. 2000. Ore Deposits and Mantle Plumes. Kluwer Academic Publishers. Dordrecht, The Netherlands
23. Head, J. and J. Mustard. 2006. Breccia Dikes and Crater-Related Faults in Impact Craters on Mars: Erosion and Exposure on the Floor of a 75-km Diameter Crater at the Dichotomy Boundary. Special Issue on Role of Volatiles and Atmospheres on Martian Impact Craters Meteoritics & Planetary Science
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25. Segura, T, O. Toon, A. Colaprete, K. Zahnle. 2001. Effects of Large Impacts on Mars: Implications for River Formation. American Astronomical Society, DPS meeting#33, #19.08
26. Segura, T, O. Toon, A. Colaprete, K. Zahnle. 2002. Environmental Effects of Large Impacts on Mars. Science: 298, 1977-1980.
27. Cabrol, N. and E. Grin. 2001. The Evolution of Lacustrine Environments on Mars: Is Mars Only Hydrologically Dormant? Icarus: 149, 291-328.
28. Fassett, C. and J. Head. 2008. Open-basin lakes on Mars: Distribution and implications for Noachian surface and subsurface hydrology. Icarus: 198, 37-56.
29. Fassett, C. and J. Head. 2008. Open-basin lakes on Mars: Implications of valley network lakes for the nature of Noachian hydrology.
30. Wilson, J. A. Grant and A. Howard. 2013. INVENTORY OF EQUATORIAL ALLUVIAL FANS AND DELTAS ON MARS. 44th Lunar and Planetary Science Conference.
31. Newsom H. , Hagerty J., Thorsos I. 2001. Location and sampling of aqueous and hydrothermal deposits in martian impact craters. Astrobiology: 1, 71-88.
32. Schorghofer, N, et al. 2007. Three decades of slope streak activity on Mars. Icarus. 191:132-140.
34. Archived February 21, 2015, at the Wayback Machine.
36. "Mars Spirit Rover Gets Energy Boost From Cleaner Solar Panels". Sciencedaily.com. 2009-02-19. Retrieved 2012-08-04.
37. Ferris, J. C.; Dohm, J.M.; Baker, V.R.; Maddock III, T. (2002). Dark Slope Streaks on Mars: Are Aqueous Processes Involved? Geophys. Res. Lett., 29(10), 1490, doi:10.1029/2002GL014936
38. ISBN 0-517-00192-6
39. Kaylan J. Burleigh, Henry J. Melosh, Livio L. Tornabene, Boris Ivanov, Alfred S. McEwen, Ingrid J. Daubar. Impact air blast triggers dust avalanches on Mars. Icarus, 2012; 217 (1): 194 doi:10.1016/j.icarus.2011.10.026
40. "Red Planet Report | What's up with Mars". Redplanet.asu.edu. Retrieved 2012-08-04.
41. "Mars Art Gallery Martian Feature Name Nomenclature". Marsartgallery.com. Retrieved 2012-08-04.
42. "HiRISE | Craters and Pit Crater Chains in Chryse Planitia (PSP_008641_2105)". Hirise.lpl.arizona.edu. Retrieved 2012-08-04.
43. "HiRISE | Graben in Memnonia Fossae (PSP_005376_1575)". Hirise.lpl.arizona.edu. Retrieved 2012-08-04.
44. Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0. Retrieved 21 March 2011.
45. Baker, V. 1982. The Channels of Mars. Univ. of Tex. Press, Austin, TX
46. Baker, V., R. Strom, R., V. Gulick, J. Kargel, G. Komatsu, V. Kale. 1991. Ancient oceans, ice sheets and the hydrological cycle on Mars. Nature 352, 589–594.
47. Carr, M. 1979. Formation of Martian flood features by release of water from confined aquifers. J. Geophys. Res. 84, 2995–300.
48. Komar, P. 1979. Comparisons of the hydraulics of water flows in Martian outflow channels with flows of similar scale on Earth. Icarus 37, 156–181.
49. Raeburn, P. 1998. Uncovering the Secrets of the Red Planet Mars. National Geographic Society. Washington D.C.
50. Moore, P. et al. 1990. The Atlas of the Solar System. Mitchell Beazley Publishers NY, NY.
51. Carr, M. 1979. Formation of martian flood features by release of water from confined aquifers. J. Geophys. Res. 84: 2995-3007.
52. Hanna, J. and R. Phillips. 2005. Tectonic pressurization of aquifers in the formation of Mangala and Athabasca Valles on Mars. LPSC XXXVI. Abstract 2261.

External links

• Lpi.usra.edu
• Ralphaeschliman.com
• Uapress.arizona.edu

Quadrangles on Mars
MC-01 Mare Boreum (features)
MC-05 Ismenius Lacus (features)				MC-06 Casius (features)				MC-07 Cebrenia (features)				MC-02 Diacria (features)				MC-03 Arcadia (features)				MC-04 Acidalium (features)
MC-12 Arabia (features)			MC-13 Syrtis Major (features)			MC-14 Amenthes (features)			MC-15 Elysium (features)			MC-08 Amazonis (features)			MC-09 Tharsis (features)			MC-10 Lunae Palus (features)			MC-11 Oxia Palus (features)
MC-20 Sinus Sabaeus (features)			MC-21 Iapygia (features)			MC-22 Mare Tyrrhenum (features)			MC-23 Aeolis (features)			MC-16 Memnonia (features)			MC-17 Phoenicis Lacus (features)			MC-18 Coprates (features)			MC-19 Margaritifer Sinus (features)
MC-27 Noachis (features)				MC-28 Hellas (features)				MC-29 Eridania (features)				MC-24 Phaethontis (features)				MC-25 Thaumasia (features)				MC-26 Argyre (features)
MC-30 Mare Australe (features)