These cores show all the various environments of deposition that existed during Pennsylvanian time in southeastern Utah and the diagenetic changes that have occurred over the millions of years since and how those events affect oil production. Additionally, the rocks in cores indicate sea level fluctuations and cyclicity, important factors in understanding differences in oil production from one well to another and identifying new drilling locations.

This article is the second in a series of articles planned to highlight exceptional examples of the diverse geologic cores available at the Utah Geological Survey’s (UGS) Utah Core Research Center (UCRC) (see Survey Notes, vol. 46, no. 3). As well as being used for research purposes, these cores, obtained through UGS projects and generous industry donations, are used for teaching geology students and training industry professionals, particularly those who search for oil and gas.