McCASKILL, JR., JERRY GLEN
The Eola fault bisects the deep portion of the Eola oil field (T 1 N, R 2 and 3 W., Garvin County, OK). At least 9 wells cut the fault and more than 200 wells within a mile of the fault define local stratigraphic relationships on either side. Within the eight miles of control in the Eola field, the fault is a linear steeply southwest dipping fault that trends N75-80W with 1500 feet of normal separation to the east and 2000 feet of reverse separation to the west. Juxtaposition of markedly different stratigraphy across the fault cannot be explained by pure dip-slip deformation, but are consistent with left-lateral displacement. More specifically offset of contour lines across the fault on isochore maps of units in the Sycamore, Hunton, and Tulip Creek Formations (based on a 650 well study) all indicate a left-lateral, strike-slip motion of 16 miles.
Data presented here indicates that the Eola fault has 16 miles of left-lateral strike-slip and plunges 3 degrees to the west, with less than 0.5 mile of either reverse or normal displacement, all of which makes interpretation of the fault consistent with a wrench fault model. Other fault models may be also explain the large strike-slip component of displacement, but any model that fails to account for a large strike-slip component will automatically be inconsistent with the well constrained data from the Eola field.
AAPG Search and Discovery Article #90944©1997 AAPG Mid-Continent Section Meeting, Oklahoma City, Oklahoma