It is fascinating to see how much geological history the team has been able to uncover with the various point measurements and a stratigraphic analysis. The best summary I know of is in this article in Science (http://www.sciencemag.org/content/350/6257/aac7575.abstract?...), which documents the discovery of stream beds feeding an ancient lake within Gale crater, river delta formations with progressively finer sediments, and small eroded canyons. It's impressive work.

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