We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Sources of Clay‐Rich Sediment in Eberswalde Crater, Mars With Implications for Biopreservation Potential.
- Authors
Hughes, C. M.; Rice, M. S.; Barnhart, C. J.; Swanson, T. E.; Pfeiffer, A. M.; Goudge, T. A.
- Abstract
The Eberswalde crater paleolake system on Mars is home to an intact source‐to‐sink fluvial system where a catchment terminates in a river delta deposit. Through analysis of topographic and hyperspectral data from multiple geographic regions, we test the hypothesis that the smectites found within the Eberswalde deposit formed during the Noachian (i.e., >3.5 Ga) in the subsurface and are fluvial detritus transported during the Hesperian (i.e., 3.5–2.0 Ga). We find that the spectra from four pertinent regions (northwest Noachis Terra, Holden crater, and the Eberswalde watershed and delta deposit) are consistent with each other, and most consistent with Fe/Mg smectite clays, namely nontronite and saponite. This points to a detrital origin for the clays observed within Eberswalde crater. Analysis of the watershed also indicates that they likely formed within the subsurface, which previous studies suggest is the location most amenable to the preservation of evidence of past life on Mars. Furthermore, the presence of detrital clays, and not authigenic, indicates that the lake was ∼neutral‐pH and a potentially habitable environment. Taken together, these observations indicate that: (a) within Eberswalde crater is a delta deposit that formed in a habitable environment, (b) that the deposit is composed of minerals that formed during the most habitable period in Mars' history, and (c) those minerals formed in an environment with strong potential to preserve evidence of life. Lastly, the similarities between the Eberswalde fluvial system and the Jezero system make it a compelling site as a standard of comparison by NASA's Perseverance Rover. Plain Language Summary: The geology of Eberswalde crater, Mars, indicates that it was once home to a neutral‐pH, habitable lake early in Mars' history (about 2.0–3.5 billion years ago). The clay minerals that were deposited by the river that filled the lake likely formed in wet‐subsurface conditions earlier in Mars' history (earlier than 3.5 billion years ago). Wet‐subsurface conditions early in Mars' history are thought to be the time and place that were most conducive to life on the Red Planet. Thus, the geologic evidence in and around the Eberswalde crater indicates that it has a strong possibility of preserving evidence of past life on Mars, if life ever existed there. Notably, this deposit, rich in biopreservation potential, is remarkably similar to the deposit in Jezero crater, where NASA's Perseverance Rover is currently exploring, which makes it a strong candidate for comparison to the Jezero crater system. Key Points: Detrital clays within the Eberswalde crater delta deposit point to an ancient neutral‐pH habitable lacustrine environmentDelta deposit sediment was likely sourced from the Noachian subsurface, a high biopreservation potential environmentThe clay‐rich river delta deposit at Eberswalde crater parallels that of Jezero crater, the current home of NASA's Perseverance Rover
- Subjects
LIFE on Mars; MARS (Planet); SAPONITE; LUNAR craters; CLAY minerals; SEDIMENTS; WATERSHEDS
- Publication
Journal of Geophysical Research. Planets, 2023, Vol 128, Issue 4, p1
- ISSN
2169-9097
- Publication type
Article
- DOI
10.1029/2022JE007545