Subsurface Reflectors Detected by SHARAD Reveal Stratigraphy and Buried Channels Over Central Elysium Planitia, Mars

Abstract

The interior morphology of Cerberus Fossae consists of a steep, layered upper slope and a gentler lower slope, which are presumably composed of exposed bedrock and talus, respectively (Plescia, 2003). Various landforms observed in this region have resulted in several hypotheses as to the origin of the Cerberus plains material, from a purely aqueous origin to a purely volcanic one. For example, Athabasca Valles is thought to have been carved by a high-discharge flood of water based on streamlined islands, notches on the sides of the breach hanging valleys and a low number of tributaries, while other authors have argued that this channel might be carved by fluid lava, which is supported by fissure vents (

Revealing Elysium Planitia's Young Geologic History: Constraints on Lava Emplacement, Areas, and Volumes

“…This western extent of Marte Vallis was previously detected by Xiong et al. (2021). However, the channel is much shallower than the authors suggested due to the fact that valley is infilled by lava (permittivity of 7.8) and not ice‐rich material, which would have a permittivity of ∼3.…”

“…Mapping out the extent of this reflector shows that it creates the interface of the lava flow to what is likely the underlying RV 1 unit, thus representing a large but shallow buried valley system visible in the subsurface DTM (Figure 10). This western extent of Marte Vallis was previously detected by Xiong et al (2021). However, the channel is much shallower than the authors suggested due to the fact that valley is infilled by lava (permittivity of 7.8) and not ice-rich material, which would have a permittivity of ∼3.…”

“…Proposed flow materials in Elysium Planitia include lava (e.g., Jaeger et al, 2007Jaeger et al, , 2010Keszthelyi et al, 2004;Voigt & Hamilton, 2018), ice (e.g., Murray et al, 2005;Xiong et al, 2021), and periglacial deposits (e.g., Balme & Gallagher, 2009;Ramsdale et al, 2015). Findings in support of volatile-rich materials on the surface or subsurface include morphological observations of fluvial features and large outflow channels (e.g., Burr & McEwen, 2000;Burr et al, 2002), a few terraced craters, locally exposed ice in crater ejecta of a recent impactor (on 24 December 2021; Posiolova et al, 2022), volcanic rootless cones (VRCs; Fagents & Thordarson, 2007;Fagents et al, 2002;Frey, 1987;Hamilton et al, 2010;Lanagan et al, 2001;Noguchi & Kurita, 2015), as well as low permittivities in the Cerberus Plains (Xiong et al, 2021). The following sections discuss: (a) the origin of the surface material (i.e., the role of lava vs. ice); (b) possible sources for water; (c) emplacement styles; and (d) lava volumes and relative estimates on effusion rates.…”

“…There have been two recent papers by Xiong et al. (2021) and Harish et al. (2023) discussing the material properties in Elysium Planitia analyzed by SHARAD.…”

3d Multi-Resolution Mapping of Mars Using Casp-Go on Hrsc, Crism, CTX and Hirise

“…Where possible, these CTX 3D products were co-registered to HRSC 3D products, where they had been publicly released [6]. Subsequently, very limited HiRISE DTM+ORI products [8], 35 HRSC image strips adjusted to MOLA DTM, covering the SPRC where available in the same season [9] and 82 HRSC and some 1,763 CTX stereo-pairs were processed covering the whole of the Valles Marineris area. This resulted in an 82-orbit HRSC mosaic where, in place of bundle block adjustment, a joint 3D point cloud and image co-registration using B-Spline fitting was performed to the reference MOLA DTM to eliminate both 3D shifts and high-frequency jitter effects, see previous section [3].…”