Eolian controlled modification of the martian south polar layered deposits

• Published in: Icarus
• Main Authors: Koutnik, Michelle R., Byrne, Shane, Murray, Bruce C., Toigo, Anthony D., Crawford, Zane A.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Elsevier 2005
• Subjects: Mars; surface; Ices; Wind; Polar; Fenton; Hallet; Polar Science
• Online Access: https://doi.org/10.1016/j.icarus.2004.09.015

Data from the Mars Orbiter Laser Altimeter (MOLA) and Mars Orbiter Camera (MOC) aboard the Mars Global Surveyor (MGS) mission and the Thermal Emission Imaging System (THEMIS) aboard the Mars Odyssey mission have revealed unique surface features in a particular region of the South Polar Layered Deposits (SPLD). The dominant morphology is large-scale quasi-parallel grooves that extend for hundreds of kilometers with only tens of meters of vertical relief, that we have termed here the "Wire Brush" terrain. The grooves are also transected by disjointed, yet roughly continuous, low-relief sinuous ridges that cross roughly perpendicular to the trend-direction of the large-scale grooves and show only tens of meters of relief. We interpret these ridges to be eroded remnants of folded layers. At the northern end of the large-scale grooves there are non-symmetric mounds. They are frequently preceded by a significant depression and/or trailing grooves that are parallel to the Wire Brush trend. We find that a two-stage process involving winds that intermittently remove a low-density crust exposing the underlying ice to ablation is the interpretation that best explains the multitude of features observed here. These features appear to be currently inactive indicating higher winds in previous epochs. © 2004 Elsevier Inc. Received 9 March 2004; revised 27 August 2004. We thank Oz Pathare (Caltech), Bernard Hallet (University of Washington), Eric Kolb (University of Arizona), and Ken Tanaka (USGS) for their contributions and useful discussions. We are grateful to Lori Fenton and an anonymous reviewer for detailed constructive reviews that greatly improved this manuscript.