LOW-CENTRED POLYGONS, “WET” GULLIES AND THE LATITUDE-DEPENDENT MANTLE: MAPPED EVIDENCE OF LANDSCAPE MODIFICATION IN AND AROUND THE ARGYRE IMPACT BASIN OF MARS BY FREEZE-THAW CYCLING
Here, we present a new geological map of the Argyre region (~290-3600 E; ~30-720 S) that integrates these observations. The map plots the spatial convergence of the LCPs, “wet” gullies and the putative LDM at the middle to the high (near-polar) latitudes of the Argyre region and shows that the landform triumvirate overlies geological units of all ages. Hitherto, the presence of LCPs has been reported only fleetingly in the literature and only in as much as they have been observed in a few Late Amazonian Epoch thermokarst-like depressions in mid-Utopia Planitia. However, the LCPs observed by us are widespread in the Argyre region and their spatial convergence with the “wet” gullies and putatively ice-rich LDM suggests that freeze-thaw cycling could have enjoyed a far greater extent and range in this area of Mars than has been thought possible.