These formations, known as the Cincinnatian Series, are approximately 200 meters (600 feet) thick and are composed of alternating thin to very thin bedded, gray, fossiliferous limestone and blue-gray ...

Limestone is often used for fireplace surrounds since it tends to cost a bit less than other natural stone materials, while still boasting a high level of durability. Similarly, quartzite can be a ...

Point Bar Features Larger fragments of limestone and weathered shale are common, as are individual fossils weathered out of their enclosing rocks. Cut Bank Features A close-up view of the cut bank ...

Although black shale is the dominant lithology, it also contains lighter shales and interbedded limestone layers due to sea level variation during its deposition almost 400 million years ago.

A sandstone and shale cap, as thick as 50 feet in places, acts as an umbrella over limestone ridges. The umbrella leaks at places called sinkholes, from which surface water makes its way ...