Subglacial water on Mars Options

[ngunn]

This topic has been discussed here over a spread of time and in various threads but not recently, I think. This article might be a good way to kick off some more discussion from a present day perspective if anyone's interested:
https://www.sciencedaily.com/releases/2020/...00803120154.htm

[serpens]

dburt, I've seen 'impact gardening' used to describe your hypotheses when reading over some of the past contributions on this and other forums, but I am not sure where. For some reason it struck a chord and no disrespect was intended. I don't think anyone would argue that impact effects, both base surge and ejecta did not contribute significantly to stratification, as did volcanism, aeolian, fluvial and lacustrine influences. As far as I am aware impact effects have been considered in analysis of rover investigations since the beginning. For example Frakik, Grotzinger and Edgar "Potential Recognition of Accretionary Lapilli in Distal Impact Deposits on Mars: A Facies Analog Provided by the 1.85 Ga Sudbury Impact Deposit". If I may quote from the abstract to the paper "While no impact-induced base surge deposits have been confirmed on Mars, it is likely that they will one day be discovered, and it is important to establish criteria for their recognition in the rock record". Personally I find the evidence for fluvial, deltaic and lacustrine deposition in Gale Crater compelling. The forthcoming contribution from Perseverance will no doubt provide another piece of the jigsaw puzzle.