Landform assemblage in Isidis Planitia, Mars: Evidence for a 3 Ga old polythermal ice sheet

A 3 Ga old polythermal ice sheet in Isidis Planitia, Mars: Dynamics and thermal regime inferred from numerical modeling

“…Adopting the assumption from Guidat et al (2015), that the presently observable landforms on the floor of Isidis Planitia are subglacial remnants, we assume that the surface topography of the Isidis region has not changed substantially over the past 3 Ga. We assume the bedrock topography to be fixed throughout the simulation, ignoring thus a possible deformation of the lithosphere due to isostatic compensation of the (modeled) ice sheet.…”

“…A fluvio-glacial origin has also been proposed for the southern part of the peripheral network of Linear Depressions and Sinuous Ridges . Guidat et al (2015) recognized a distinctive, concentric, organization of the landforms in Isidis Planitia and interpreted this landform assemblage as a glacial landsystem inherited from the pres- Guidat et al, 2015). a) Mosaic of visible CTX images (P03 002400 1887 XN 08N276W//P06 003178 1888 XN 08N276W//B07 012276 1887 XN 08N276W//B17 016311 1903 XN 10N276W), illustrating the typical morphology and the spatial organization of Arcuate Ridges.…”

“…Building upon previous works (Grizzaffi and Schultz, 1989;Lockwood et al, 1992;Kargel et al, 1995), Guidat et al (2015) interpreted the landform assemblage in Isidis Planitia as a glacial landsystem inherited from a polythermal, 3 Ga old, glaciation of the entire basin. This interpretation apparently supports the results of General Circulation Models (GCMs), which predict that surface ice may have accumulated near the martian equator in the past (Mischna et al, 2003;Levrard et al, 2004;Forget et al, 2006;Madeleine et al, 2009;Wordsworth et al, 2013).…”

“…Our conclusions are summarized in Section 6. Guidat et al, 2015). The Thumbprint Terrain (red) comprises a ring where Arcuate Ridges and Aligned Cones (both interpreted as relicts of ribbed moraines formed below wet-based ice) are organized in whorl-shaped patterns centered on an area located in the NW part of the basin.…”

Probing the Hidden Geology of Isidis Planitia (Mars) with Impact Craters

“…New evidence for long-term water-related activity and climatic changes based on recent higher resolution datasets has led to a reappraisal of Isidis Planitia as a site for future landing missions [24]. Morphologies along the Deuteronilus paleoshoreline in south Isidis Planitia suggest that in the Late Hesperian/Early Amazonian a frozen sea existed in the basin, with the ice eventually melting and sublimating, leaving traces of past subglacial erosion and deposition on the floor of Isidis Planitia [25][26][27].…”