User:SPACUser16/Lobate debris apron

Recent Observations:
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. 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.

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. 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. 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. 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.

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.