Tuesday, January 28, 2014

Rock photos

I have been tweeting these. I should post some of the prettiest here, like I used to.

Here we have a brown ooid in a gray limestone. The ooid was exposed & weathered, then re-buried. The other photo shows micropellets in an oolitic rock. Pellets=poop, but these miniatures are probably microbially mediated precipitates. They're so small, most critters are just too big to be the culprits.