Structural Characterization of the Wilzetta Fault Zone; Lincoln, Pottawatomie, and Creek Counties, Oklahoma
Abstract
A subsurface structural study was conducted to characterize the structure and seismicity near the Wilzetta fault of northeastern Oklahoma. To determine the structural characteristics of the Wilzetta Fault Zone (WFZ); well log, earthquake, geomagnetic, gravitational, and seismic data were examined. The study area includes southern Pottawatomie County, southern and eastern Lincoln County, and northwestern Creek County. Detailed study is focused on the vicinity of recent seismicity in southern Lincoln County. The study shows that the ∼N25-30E trending WFZ is a relatively long, narrow zone of high angle normal, strike-slip, and reverse faults. Fault cuts in wells are rare and traces are inferred from vertical offset, changes in dip, variation in formation thickness, and structural trends. Deformation occurred from at least early Mississippian to the lower Pennsylvanian (Missourian).). Throw reversal, pop-up features, and a series of en echelon faults are evident along the strike of the Wilzetta. The subsurface en echelon faults along the WFZ each strike ∼N55-60E, approximately 30° from the strike of the Wilzetta fault. Structural patterns and earthquake data indicate that right-lateral strike-slip movement has occurred along both the Wilzetta and the subsurface en echelon faults. Seismicity is confined to basement depths on a previously undefined right-lateral strike-slip (here termed the ‘Meeker-Prague’) fault. The Meeker-Prague fault strikes ∼N55E and obliquely
AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015