Reull Vallis, pictured below, displays these deposits.[1] Sometimes the lineated floor deposits show a chevron pattern which is further evidence of movement. The picture below taken with HiRISE of Reull Vallis shows these patterns.

Recent Observations:[edit]

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Recent analyses of the Nereidum Montes (~35°- 45°S, ~300° - 330°E), and Phlegra Montes (NNE - SSW, between latitudes 30° - 52°N) mountain ranges of Mars have revealed terrains rich in Viscous Flow Features (VFFs), a Cyro-geomorphological group of which Lobate Debris Aprons (LDAs) are a sub-class. In a 2014 study, 11,000 VFFs have been recorded between 40° and 60° in northern and southern latitudes, with a 2020 study identifying approximately 3,348 VFFs in the Nereidum Montes range.[2][3] These LDAs were more extensive and older VFF features (100 s of Ma) in the range, with the vast majority located in impact craters and surrounding massifs.[2]

Water-ice to lithic ratios of 9:1 were recorded for LDAs by the Mars Reconnaissance Orbiter (MRO), with Berman’s (2020) study presenting Nereidum Montes as possibly containing more water-ice rich LDAs, than other locations in the mid-latitude band.[2][4] Studies have estimated that LDAs could reach from 10’s up to 390 meters in thickness, with anywhere from 1 m to 10 m of overlying regolith preventing sublimation.[4][5][6] Late Amazonian glaciation may have occurred in the mid-latitudes due to water-ice emplacement from higher latitudes. This glaciation may have occurred during high obliquity periods in Mars past.[2][6][7][8] Some of these LDAs are overlain with another class of viscous ice flows that is smaller, and younger (10 s of Ma) called Glacial-Like Flows (GLFs). Some 320 of these superposed GLFs (SGLFs) have been found implying successive glaciation periods.[8]

The datasets utilized in these studies included MRO Context Camera (CTX; ~5–6 m/pixel), High-Resolution Imaging Science Experiment (HiRISE) (~25 cm/pixel) images, MRO Shallow Radar (SHARAD), 128 pixel/degree (~463 m/pixel) Mars Global Surveyor (MGS), Mars Orbiter Laser Altimeter (MOLA), Digital Elevation Modelling (DEM), 100 m/pixel THEMIS Day and Night IR mosaics, and the GIS-based (ESRI ArcGIS Desktop) software.[2][5][6][7][8]

  1. ^ "Archived copy". Archived from the original on 2010-06-17. Retrieved 2010-12-19.{{cite web}}: CS1 maint: archived copy as title (link)
  2. ^ a b c d e Berman, Daniel C.; Chuang, Frank C.; Smith, Isaac B.; Crown, David A. (2021-02-01). "Ice-rich landforms of the southern mid-latitudes of Mars: A case study in Nereidum Montes". Icarus. 355: 114170. doi:10.1016/j.icarus.2020.114170. ISSN 0019-1035.
  3. ^ Levy, Joseph S.; Fassett, Caleb I.; Head, James W.; Schwartz, Claire; Watters, Jaclyn L. (2014). "Sequestered glacial ice contribution to the global Martian water budget: Geometric constraints on the volume of remnant, midlatitude debris-covered glaciers". Journal of Geophysical Research: Planets. 119 (10): 2188–2196. doi:10.1002/2014JE004685. ISSN 2169-9100.
  4. ^ a b Schmidt, Louise Steffensen; Hvidberg, Christine Schøtt; Kim, Jung Rack; Karlsson, Nanna Bjørnholt (2019/12). "Non-linear flow modelling of a Martian Lobate Debris Apron". Journal of Glaciology. 65 (254): 889–899. doi:10.1017/jog.2019.54. ISSN 0022-1430. {{cite journal}}: Check date values in: |date= (help)
  5. ^ a b "Landforms indicative of regional warm based glaciation, Phlegra Montes, Mars". Icarus. 355: 114173. 2021-02-01. doi:10.1016/j.icarus.2020.114173. ISSN 0019-1035.
  6. ^ a b c Gupta, Vanshika; Gupta, Sharad Kumar; Kim, Jungrack (2020/1). "Automated Discontinuity Detection and Reconstruction in Subsurface Environment of Mars Using Deep Learning: A Case Study of SHARAD Observation". Applied Sciences. 10 (7): 2279. doi:10.3390/app10072279. {{cite journal}}: Check date values in: |date= (help)CS1 maint: unflagged free DOI (link)
  7. ^ a b Hepburn, A. J.; Ng, F. S. L.; Holt, T. O.; Hubbard, B. (2020). "Late Amazonian Ice Survival in Kasei Valles, Mars". Journal of Geophysical Research: Planets. 125 (11): e2020JE006531. doi:10.1029/2020JE006531. ISSN 2169-9100.
  8. ^ a b c Hepburn, A. J.; Ng, F. S. L.; Livingstone, S. J.; Holt, T. O.; Hubbard, B. (2020). "Polyphase Mid-Latitude Glaciation on Mars: Chronology of the Formation of Superposed Glacier-Like Forms from Crater-Count Dating". Journal of Geophysical Research: Planets. 125 (2): e2019JE006102. doi:10.1029/2019JE006102. ISSN 2169-9100.