Appendix I: Fusulinid Biostratigraphy of Upper Pennsylvanian Cores from Cheyenne County, Nebraska

Abstract

Other cores were examined from the study area, but they covered parts of the stratigraphic section that did not have any fusulinid-bearing horizons. From the four cores analyzed here, over 100 petrographic thin-sections were examined for fusulinid biostratigraphy, and an additional 90 oriented-fusulinid thin-sections were made from 50 fusulinid-bearing samples. Also, data from an Amoco fusulinid biostratigraphic chart (made by George Verville in the 1980's) from a nearby fifth cored well, the Ohio #3 Pahl, Cheyenne County, Nebraska, were evaluated and correlated with new data from the other four cored wells. The Ohio #3 Pahl fusulinid dataset was particularly significant because the cores included lower Virgilian and Desmoinesian intervals, which had not been cored in the four newly-sampled wells. Another Amoco fusulinid chart with good data from the Shell #A-16 Green in adjacent Logan County, Colorado, was also evaluated and correlated with data from the new wells, and was instrumental in constructing a reliable Pennsylvanian fusulinid zonation for the study area.