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Here's a link to an article about the sliding rocks: http://geology.com/articles/racetrack-playa-sliding-rocks.shtml
Forget the boulder tracks...What are those ODD patches above that? They look almost like holes left by glacial ice-block melt!No...wait...THOSE ARE PLATEAUS!!! Apparently the remnants of a hard surface that was pulverized except for a few spots. That's just as intriguing as to what could have left just those areas elevated whilst everything else "eroded" away around them.
More boulders and tracks.
It has a pattern of TWO bounces close together, followed by a longer pause, that hints at an irregularly shaped boulder.