Noachian Proglacial Paleolakes on Mars: Regionally Recurrent Fluvial Activity and Lake Formation within Closed-source Drainage Basin Craters

Abstract

A body of geologic evidence suggests that Noachian-aged craters on Mars were modified primarily by runoff from rainfall in a warm and wet early Mars climate. Although melting and runoff of frozen water ice have been suggested as plausible alternatives, supporting geomorphic evidence of Noachian glaciation on Mars has been elusive. We previously identified a Noachian-aged crater in the southern highlands that contained evidence of glacially derived fluvial and lacustrine features but was hydrologically disconnected from its surroundings. This closed-source drainage basin (CSDB) crater and proglacial paleolake provided the first candidate evidence of Noachian cold-based glaciation on Mars. Here, we describe a second nearby CSDB crater that contains similar evidence of glacial melting leading to the formation of proglacial fluvial channels and paleolakes on the crater floor. This new evidence suggests that CSDB formation was occurring episodically at regional scales throughout the Late Noachian and into the Early Hesperian. Recurrent episodes of glacial melting are consistent with climate model predictions of a cold and icy early Mars highlands with limited melting of glacial ice during periods of punctuated warming.

Constraining Early Mars Glacial Conditions From Paleodischarge Estimates of Intracrater Inverted Channels

“…Ridge bases were identified using morphologic (visible transitions between ridge and crater floor units) and/or topographic (inflection point) indicators. For calculations of contributing areas from glacial alcoves, we used a 5 m/pix Context Camera (CTX; Malin et al., 2007) DEM from our previous studies of crater B (Boatwright & Head, 2021, 2022) to generate a series of hydrologic data products (flow direction and flow accumulation) in ArcMap. The stereo data products were supplemented with the corresponding CTX and HiRISE visible images.…”

“…Many free‐standing sinuous ridges on Mars have been interpreted as topographically inverted fluvial channel or channel belt deposits (Burr et al., 2010; DiBiase et al., 2013; Pain et al., 2007; Williams, Irwin et al., 2013; Williams et al., 2009), suggesting the presence of flowing liquid water in the early period of Mars geologic history (e.g., Carr, 1995; Craddock & Howard, 2002; Howard et al., 2005; Hynek et al., 2010). We previously identified inverted fluvial channels within the Noachian‐aged crater “B” (20.3°S 42.6°E) in the circum‐Hellas highlands (Boatwright & Head, 2021, 2022). Unlike the inverted channels found elsewhere on Mars, the drainage that formed these inverted channels appears to be derived from within the crater itself, that is, a closed‐source drainage basin (CSDB).…”

Data‐Driven Fuzzy Weights‐Of‐Evidence Model for Identification of Potential Zeolite‐Bearing Environments on Mars

“…The database consists of the locations of 205 closed‐basin lakes (Goudge et al., 2015) and 220 open‐basin lakes (Fassett & Head, 2008; Goudge et al., 2012). However, this database does not contain potential paleolakes without inlet valleys (like Columbus crater; Wray et al., 2011), possibly fed by groundwater (e.g., Boatwright & Head, 2021, 2022; Hargitai et al., 2018; Wray et al., 2011). This type of paleolake may have also been common on early Mars.…”