Natural gas in Arkoma basin of Oklahoma and Arkansas


ABSTRACT The Arkoma Basin is in E.-SE. Oklahoma and in W.-central Arkansas. The deepest part of this arcuate trough is adjacent to the Ouachita Mt. system where the sedimentary column is estimated to be 30,000-ft thick. Rocks in the basin have been highly deformed by a combination of forces. Evidence indicates that some of these faults were growing contemporaneously with deposition of Lower Pennsylvanian beds. Early Permian mountain building on the south compressed Arkoma Basin beds into a series of long, narrow, E.-W. anticlinal and synclinal folds. Overthrusting along anticlinal axes near the mountain front is common. Most of the gas production in the Arkoma Basin is from lenticular, fine-grained sandstone within the Atoka sequence. The entire Atoka sequence is estimated to be 20,000 ft thick along the mountain front in Arkansas. The Arkoma Basin is essentially a dry-gas province with the gas being approx. 95% methane. To date there are about 25 gas-producing zones in the basin, ranging in age from Pennsylvanian to Ordovician. (23 refs.)