SEDIMENTARY STRUCTURES
Sedimentary structures are features in sedimentary rocks that provide information about the physical environment conditions present when sediments were originally deposited. They permit geologists to determined whether, for example, a particular sandstone was deposited in an ancient desert environment, a river environment, a beach environment, a shallow ocean environment, or wherever.
Some sedimentary structures are not very informative. Others provide exceedingly specific information about the original depositional environment.