Sandstone concretion


Sandstone concretion

Sandstone concretion with shell fossil

Lithogenous and biogenous sedimentary rock.
This sandstone concretion preserves a large clam shell fossil in its center.
Miocene age, Anza-Borrego desert area, San Diego County, California.

https://gotbooks.miracosta.edu/rocks/sedimentary/26.html

2/2/2021