“Studying these buttes up close has given us a better understanding of ancient sand dunes that formed and were buried, chemically changed by groundwater, exhumed and eroded to form the landscape that we see today,” said Curiosity project scientist Ashwin Vasavada of NASA’s Jet Propulsion Laboratory.

This image shows the Stimson formation, ancient sandstone that formed by wind-deposited sand after the formation of lower Mount Sharp.

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