Description
- Uperocrinus pyriformis & Eretmocrinus
- Mississippian Age
- Burlington Formation
- Pike County, Missouri
- Specimen measures approx. 2 3/4″ x 3 7/8″
The Burlington Formation is a marine limestone, found in rock layers laid down during the Mississippian Period (325-360 million years ago).  The Mississippian Period was relatively short-lasting only 35 million years-and its fossil record is almost entirely marine (Thompson, 1982).  This is due to the flooding of North America called the Kaskaskia transgression, which began during the Devonian Period (380-450 million years ago). This was interrupted at the end of the Devonian Period by partial regression, but deposition continued uninterrupted into the Mississippian Period. The Kaskaskia Sea reached its greatest extent about the middle of the Mississippian Period, and late Mississippian sedimentary rocks of the basins mark its recession. This recession also marks the boundary between the Mississippian and Pennsylvanian
Periods in the North America (Clark and Stern, 1960). By: Richard Gottfried
