Winter is a good time to study the geology and landscape of our home planet. Barren trees and flattened grasslands yield broader vistas and we are not distracted by the abundance of plant and animal life that characterize our warmer months. Those interested in hunting for fossils of early marine life should consider a visit to my home town of Cincinnati, Ohio.
The Ordovician shales and limestones of Greater Cincinnati were deposited in shallow seas, some 500 million years ago (60 million years before plants first colonized the land). An upward bowing of the deeper Precambrian rocks, known as "the Cincinnati Arch," has kept these ancient marine sediments near the surface, where they are now exposed by roadcuts and stream erosion. Famous for their cargo of bryozoan, brachiopod and trilobite fossils, these rocks extend into southeastern Indiana and down through the Bluegrass region of northern Kentucky.
