Abstract: Three Dimensional Seismic Interpretation from the Triangle Zone Between the Ouachita Mountains and Arkoma Basin, Hartshorne, OK

M. VAlderrama, K. C. Nielsen, G. A. McMechan

The boundary between the frontal Ouachitas fold and thrustbelt and the foreland Arkoma basin has been interpreted as a triangle zone. 3-D seismic reflection data from this triangle zone show details not recognized in conventional 2-D seismic data. The data indicates that the frontal Kiowa syncline in the Arkoma basin has been passively uplifted by blind thrusting at deeper levels. Blind thrusting takes place at two levels: the Morrowan Wapanucka Formation and the Silurian Hunton Formation. Detachments for the thrusting in the Wapanucka Formation are in the Springer Shale and the Woodford Formation. The thrusts offsetting the Hunton Formation have detachments in the Simpson Group and possibly in the Arbuckle Group or even deeper. Horizontal shortening in the Wapanucka Formation ranges rom tens of meters to a few kilometers, and in the Hunton Formation from tens of meters to a few hundred of meters.

Four reflectors were interpreted: a reflector in the lower Atoka Formation, two repeated Wapanucka limestone sections and the Hunton Formation. All of the surfaces exhibit the same geometry with their fold axis plunging to the southwest. The surface geometry and fold axis data suggest that the first thrusting was in the Wapanucka Formation and later in the Hunton Formation. Faulting in the Hunton Formation has been traditionally interpreted as normal, although basement-involved reverse faults, such as the Carbon fault, have been mapped. The interpretation of some individual in lines or crosslines may also show normal faults, but the interpretation of the whole 3-D survey support the proposed compression in the older sequence.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994