Models for Arbuckle Dolomitization and It's Ramifications to Local Structure Part A

Kurt Rottmann and Steve Hadaway

The Arbuckle Group is almost entirely composed of dolomite and limestone. Dolomite, within this Group and other Early Paleozoic deposits, is one of the commonest sedimentary materials. However, the question remains, how did these dolomites originate? Certain areas of the mid-continent, notably Osage County, Oklahoma, have Pre-Cambrian surfaces that have been strongly eroded which created numerous geomorphic features that have been preserved by Arbuckle deposition. Compaction of the sediments, from Arbuckle through Early Pennsylvanian, occurred penecontemporaneous with deposition. However, mapping of multiple areas where structural closure is present and superimposed on a Pre-Cambrian geomorphic feature, suggests that a significant compaction event occurred either during Upper Missourian or Post-Missourian time. This compaction event resulted in a significant amount of change in structural relief to older sediments. This compaction event could have only come about from a massive volumetric decrease of a thick, mostly homogeneous sedimentary section. Late term, deep burial dolomitization of the Arbuckle Group would fit this scenario and provide the means for a massive volumetric reduction in rock volume, that when compacted, could account for the amount of structural relief observed in the Upper Missourian section of Osage County, Oklahoma. This late term deep burial dolomitization scenario could occur within specific depth/ temperature/ time windows and could potentially explain the presence of other structural closures that occur within the Mid-Continent. The Arbuckle is an important component to the Mississippian play of the Mid-Continent, due to it's ability to accommodate produced water from the Mississippian. The practice of casing above the Arbuckle and completing the Arbuckle open-hole without an effort to analyze the Arbuckle for potential pay zones is a lost opportunity and a waste of resources 

AAPG Search and Discovery Article #90176©AAPG Mid-Continent Meeting, Wichita, Kansas, October 12-15, 2013