I spotted this large striped rock found on Delaware River. Note the fossil in the first picture. What kind of rock is this?

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closed as off-topic by Jan Doggen, user12525, Fred, Erik, arkaia Aug 29 at 11:54

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The boulder appears to be dark grey fossiliferous limestone or dolostone with softer tan layers which might be: limestone or calcareous claystone/siltstone/sandstone. From the photo, the tan layers do not appear to be shale.

I have a hand specimen which is very similar from southern New Jersey. It is harder grey limestone inter-layered with light tan calcareous siltstone. enter image description here


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