Here’s a marked-up version of the image at the top, with rocks outlined in red and bones in blue:
The big rock in the middle is the original one we discovered in 2013, while the others were all found today. There are several interesting things of note here, besides the fact that so many big rocks are present. It appears that the rocks in the upper left corner may have originally been one rock that was shattered before or during Calvert deposition (there was Calvert sediment between the pieces), although we haven’t actually fitted them back together yet.
Also notice how the bones are distributed relative to the rocks. While we’re finding some bones on top of the rocks, most of them are wedged into the gaps between the rocks. So far we haven’t found any bones under the really huge rocks (although we have found bones under small and medium size rocks). That tells us a few things. The giant rocks were probably already sitting on the sea floor when the bonebed formed, although we can’t yet say how long before. But while the rocks were there, they were sticking up above the bottom, leaving gaps to be filled by Calvert sediment (and bones).
For all my talk about the rocks, we did find several interesting fossils today. Chip found a couple of unrelated vertebrae next to each other. One is a moderately large apparent mysticete vertebra that’s still in the ground:
The other is a tiny and rather unusual thoracic vertebra, apparently from an odontocete:
Fortunately all the thunderstorms missed us today, so hopefully we’ll be just as lucky tomorrow.