Paleoecology of the Devonian- Mississippian black-shale sequence in eastern Kentucky with an atlas of some common fossils.

The Devonian-Mississippian black-shale sequence of E North America is a distinctive stratigraphic interval generally characterized by low clastic influx, high organic production in the water column, anaerobic bottom conditions, and the relative absence of fossil evidence for biologic activity. The laminated black shales which constitute most of the black-shale sequence are broken by two major sequences of interbedded greenish-gray, clayey shales which contain bioturbation and pyritized micromorph invertebrates. The laminated black shales point to anaerobic conditions and the bioturbated greenish-gray shales suggest dysaerobic to marginally aerobic-dysaerobic conditions. -from US Govt Reports Announcements, 20, 1981