Analysis of closely spaced wireline logs and 1500 ft (>450 m) of whole cores from five wells within the Upper Cretaceous (Cenomanian) lower Woodbine Group in the northern part of East Texas Field, reveals complex sandstone-body architecture. This study focuses on a 12.25-mi2 (31.7-km2) north pilot area (NPA), where lowstand, coarsegrained, bedload fluvial deposits truncate an underlying succession of fluvial-dominated highstand deltaic deposits.

Two distinct depositional systems comprising significant sandstone bodies are recognized in the NPA. The lower interval is composed of a highstand, fluvial-dominated, deltaic depositional succession with a depositional framework defined by dip-elongate distributary-channel sandstones. The upper interval consists of a lowstand incisedvalley- fill succession composed of multistoried, coarse-gravel conglomerate and coarsegrained sandstone beds that truncate more than 100 ft (>30 m) of the highstand interval. Recognition of the size, shape, and distribution of sandstone bodies allows for assessment of reservoir compartmentalization and the analysis of fluid-flow pathways that can provide a geological framework for identifying potential unswept mobile oil in the East Texas Field.