Reservoir Characterization of the Pennsylvanian Cleveland Sandstone, Cleveland Field Unit, Northeastern Oklahoma
The Cleveland Field in northeastern Oklahoma has produced an estimated 50 MMBO since its discovery in 1904. This study is part of a re-evaluation of this very mature oil field by use of high-resolution reservoir data in order to identify bypassed ‘pay’ and to estimate ultimate recovery of hydrocarbons of the field. It has focused on the Middle Pennsylvanian (Desmoinesian) Cleveland Sandstone in what is now the ‘Cleveland Field Unit.’ The Cleveland Sandstone, which is approximately 120–200 ft thick, is composed of four distinct depositional units, or zones (A, B, C, and D, in descending order). Considerable oil has been produced from the B zone of the Cleveland. Yet other oil-bearing zones in the Cleveland, only subtly finer grained and more interbedded than the B zone, have been discounted because older tests and calculations from vintage logs resulted in past assessments that these sandstone bodies are effectively non-productive. However, modern tools for evaluation, along with innovative drilling and completion techniques, have rendered these same sandstones to be profitable, productive units. Zone C, which best exemplifies this re-evaluation, is highlighted here. The techniques used in this study are thought to have application in other mature fields, especially in the Mid-Continent.
AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015