The morphology of glacier-associated layered deposits on Mars

Mars is thought to have been a hyperarid desert for at least the last one billion years of its history and so water is locked up in the two polar ice caps, ground ice and an extensive band of debris covered glaciers found in the mid-latitudes. Layers expressed by the polar caps are thought to record the most recent climate cycles of Mars – up to a few tens of Ma. The debris covered glaciers are thought to date to hundreds of millions of years in age and potentially record a deeper climate record. Here, we report on the widespread occurrence of layered outcrops intimately associated with glaciated terrains in Deuteronilus Mensae and the Eastern Hellas region – two areas renowned for their extremely extensive and well-preserved debris covered glaciers. We explore the relationship between these layered outcrops and the debris covered glaciers by exploiting images and elevation data from the High Resolution Science Imaging Experiment (HiRISE) at 25 cm/pixel, Context camera (CTX) at 6 m/pixel and Colour and Stereo Imaging System (CaSSIS) at 4.5 m/pixel. Because these outcrops have similar morphology in both the northern and the southern hemisphere they point to a globally relevant process. Our aim is to test the hypothesis that these deposits represent remnant glacial deposits, which could give information of Mars climate beyond that obtainable by studying the polar caps.