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Yorktown Formation

Detailed Description

Photo shows the fossil-rich sediments of the mid-Piacenzian warm period (MPWP) that document the rapid warming and sea level rise between about 3.30 and 3.25 million years agao. The hammer is at the conformable boundary between the Rushmere (below) and Morgarts Beach (above) Members of the Yorktown Formation. 


Public Domain.