KINEMATIC DEFORMATION MODEL OF THE FRONTAL OUACHITA/ARKOMA BASIN TRANSITION ZONE IN WESTERN ARKANSAS

The Arkoma Basin is an asymmetrical peripheral foreland basin of the Ouachita Orogeny and is bounded to the south by the Ouachita Mountains and to the north by the Ozark Uplift. The stratigraphy of the Arkoma Basin is characterized by Late Devonian, Mississippian and Pennsylvanian pulses of clastic sedimentation, represented by the Stanley Formation, Jackfork Group, and Atoka Formation. The basin consists of anticlines and synclines that have broader wavelengths and shallower amplitudes moving northward away from the frontal thrust belt. This broadening sequence reflects the strain partitioning northward towards the Ozark Uplift. In western Arkansas, the transition from the highly deformed Frontal Ouachitas to the Arkoma Basin is characterized by triangle zones in two different structural levels. Our work highlights the strain partitioning from the Waldron Triangle Zone (at the leading edge thrust of the Ouachitas) through the structurally higher Washburn Triangle Zone (further northward into the Arkoma Basin).