Speaker: Rick Fritz

Subject:The Many Faces (or facies) of the “Osage” STACK Play

Bio     Richard (Rick) Fritz is a native Oklahoman who spent much of his youth around the oil patch in Osage County, Oklahoma.  His dad, granddad, great-granddad and many of his uncles worked as pumpers or roughnecks. Currently, Rick is CEO of Council Oak Resources, a new EnCap private equity start-up focused on the Midcontinent.  The goal of Council Oak Resources is to determine the best resource reservoirs and target using advanced geoscience, engineering and analytical methods.

Rick started his career in 1977 by working for Exxon (before +Mobil) in development geology in South Texas and later as an exploration geologist in the Mid-continent. Post Exxon, Rick became president of Masera Corporation and supervised major exploration research projects in the U.S., and in the Middle East and Africa.  From 1999 to 2011, Rick was the Executive Director of AAPG. He was responsible for the management of AAPG headquarters in Tulsa, Oklahoma and the oversight of numerous programs for AAPG’s 34,000+ members.  In 2011 Rick was hired to work in SM Energy Company’s new venture exploration team in Tulsa.  Rick studied active resource plays to understand the parameters that made some successful and others marginal.

Abstract     The “Osage” play reminds me of the much-used story of the elephant and the blindfolded observers.  They described it according to which part they were touching.  Within the so-called “Osage” lithostratigraphic horizon five different play types have been interpreted from wireline log characteristics and production case studies from across the Anadarko Basin.  The “Osage” is mapped throughout the Anadarko Basin and is bounded above by the “Meramec” Lime and below by the “Kinderhook” Shale or where absent the Woodford “Shale”. These lithostratigraphic horizons are often diachronous and should not be confused with Kinderhookian, Osagean, and Meramecian chronostratigraphic-aged units.  Due to its thickness and many reservoir bearing facies-types, multiple opportunities for exploration and development exist within the apparently massive “Osage” chert/carbonate section.  To understand the five proposed “Osage” plays it is important to view them in the context of the greater STACK area. The top of the “Osage” is commonly picked at the top of the first carbonate (high-resistivity) sequence below the “Meramec” siltstone/shale.  Based on sequence stratigraphic correlations to biostratigraphically dated intervals, this “false Osage” is likely Meramecian aged silty carbonate.  Alta Mesa and other companies have made good horizontal wells in this section particularly in T17N-R5,6W (Play V). The actual top of Osagean strata is likely defined by a regionally traceable flooding surface overlying an apparent unconformity at the base of the silty carbonate.  The Osagean interval is almost 500 ft. thick in Dewey County and thins southeastward to less than 50 ft. thick in eastern Blaine to less than 10 ft. in Kingfisher County.  This cherty carbonate section is distinctive and correlatable across much of the northern Anadarko Basin shelf.  The Osagean section can be divided into lower and upper intervals with similar lithologies.  The lower interval is mostly chert sometimes capped by limestone.  The upper interval shallows upward from siliceous, spiculiferous chert, to calci-sponge dominated limestone sometimes capped by an Echinoderm grainstone to packstone.  These latter grainstones can be porous such as those found in the Tapstone Krows 19-19-17 1H well in northern Dewey (Play IV).  The upper Osagean calci-spiculiferous limestone is usually tight but several wells like the Tapstone Howard 5-19-17 1H encountered tectonically fractured zones that have high initial rates of production with steep, fracture-related declines (Play III).  Some of the best producing wells are in the chert zones at the base of the upper and the lower Osagean section.  The Devon (Valpoint) Olive Lee 1H-22 (T19N-R16W, Sec. 27) produces out of the lower Osagean chert and the Council Oak Lau 1-4H and Coffey 1-7H (T17N-R13W, Secs. 4 & 7, respectively) produce out of the upper Osagean chert (Plays I & II).  The “Osage” was the tertiary target for the “Meramec”-Woodford STACK play…not any more.  These new lower Osagean discoveries in western Blaine and eastern Dewey counties from an unusual chert facies within the “Osage” has “opened-eyes” regarding production results and rate-of-return. -Council Oak Exploration Team