Comparison of Crude Oils Found in Mississippian Reservoir Rock and Potential Source Rocks in the Black Warrior Basin, Southeastern United States

Abstract

The Black Warrior basin is a Paleozoic foreland basin located between the Appalachian and Ouachita orogens in the southeastern United States. As the depositional center for both orogenies, the basin experienced maximum burial, maturation, and subsequent cessation of hydrocarbon generation during Late Permian time. The Black Warrior basin is a productive basin for hydrocarbon exploration; however, the source of the oil being produced from the Mississippian sandstone reservoirs (Carter, Hartselle, Lewis, and Gilmer) has yet to be determined. The Chattanooga and Floyd/Neal Shales have been evaluated for their source potential (Rock-Eval pyrolysis) in previous studies, and are identified as viable potential source rocks for the region. Rock samples of each of the two source rocks are analyzed, as well as crude oil from the Carter, Hartselle, Lewis and Gilmer sandstone reservoirs. By utilizing Gas Chromatography – Mass Spectrometry analyses, the distributions of aliphatic and aromatic hydrocarbons (e.g., carbon number, even/odd predominance) between the source rocks and reservoir crude oils are compared to determine the source rocks that are responsible for the crude oils. The end result is a petroleum system basin model of the Black Warrior basin that analyzes the source to reservoir pathways as well as deposition, burial timing, and maturation through the use of Petromod software. Analysis of available vitrinite reflectance, well log, and burial history data allows for a complete rendering of the migration pathways from source rock to reservoir.

AAPG Datapages/Search and Discovery Article #90259 ©2016 AAPG Annual Convention and Exhibition, Calgary, Alberta, Canada, June 19-22, 2016