MODEL FOR BEACH SHORELINE IN GALLUP SANDSTONE (UPPER CRETACEOUS) OF NORTHWESTERN NEW MEXICO.

Abstract

A model stratigraphic cross section for beach deposits in the Gallup Sandstone (Upper Cretaceous) in the Ship Rock area of northwestern New Mexico was constructed for comparison with other ancient deposits as well as with modern beaches. The model shows a lower regressive beach sandstone overlain unconformably by an upper transgressive offshore-bar sandstone. This model provides a basis for predicting the location of petroleum reservoirs, evaluating source and seal relationships, determining volumes of both the reservoir and the aquifer providing the water drive, and predicting flow patterns within the reservoir.