This evenly layered rock photographed by the Mast Camera (Mastcam) on NASA's Curiosity Mars Rover shows a pattern typical of a lake-floor sedimentary deposit not far from where flowing water entered a lake.  The scene combines multiple frames taken with Mastcam's right-eye camera on Aug. 7, 2014.  This is an example of a thick-laminated, evenly-stratified rock type that forms stratigraphically beneath cross-bedded sandstones regarded as ancient river deposits. These rocks are interpreted to record sedimentation in a lake, as part of or in front of a delta, where plumes of river sediment settled out of the water column and onto the lake floor.
Jim Secosky picked out a NASA image  NASA/JPL-Caltech/MSSS
2018-03-28
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