The structures of the Arbuckle Mountains and Ardmore Basin have long been considered definitive examples of strike-slip deformation. These interpretations are questionable, however, because estimates of the amount of strike-slip on the main fault (the Washita Valley Fault) vary from as little as 3 miles to as much as 40 miles, and both well and seismic data show that the major faults of the area dip only 40-50°.

This paper presents a series of highly constrained, balanced and palinspastically restored vertical cross sections which show that the observed structures may be entirely dip-slip compressional structures. The overall structure is that of a large scale passive duplex. The master strike-slip "propeller" fault, which appears to reverse its dip and sense of throw along strike, is interpreted as the roof and floor thrusts bounding a plunging basement wedge. The Arbuckle Anticline itself is interpreted as a fault-bend fold in the hanging-wall of the roof thrust. The apparent releasing bend in the master strike-slip fault appears to be a triangle zone in the footwall of the roof thrust. The apparent positive flower structures adjacent to the Arbuckle Anticline are interpreted as second-order, detached folds in the roof sequence of the duplex. These new interpretations suggest that many of the structural criteria thought to be characteristic of strike-slip structures, are in fact characteristic of dip-slip passive duplexes involving basement.

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