Sequence Stratigraphy and Reservoir Characterization of the V17 Interval of the Vicksburg Formation (Early Oligocene), Southern Brooks County, South Texas

The Early Oligocene Vicksburg Formation of south Texas was deposited as a prograding clastic shelf deltaic system. Reservoir quality within the Vicksburg is found to increase in the proximal portion of the delta system due to higher sand concentrations.

Growth fault movement at the time of deposition results in an intricate relationship between structure and stratigraphy. Increased accommodation space due to growth fault movement results in a complex sequence stratigraphic framework. In this study, seismic and well log data were used in conjunction to analyze stratigraphic relationships within the V17 wedge of the lower Vicksburg Formation. In the expanded portion of the depositional wedge, a higher resolution of sea level fluctuations were able to be preserved due to movement along the fault plane. These additional flooding surfaces that are not seen updip in the wedge are laterally continuous and may in fact have the characteristics necessary to provide a capillary pressure seal to compartmentalize the reservoir. Further understanding of the development of the V17 wedge enhances the overall understanding of reservoir character throughout the Vicksburg.