Dendritic drainage pattern. Cyclic transgressions and regressions led to deposition of four prominent lower Morrow sandstone members separated by shale units which are approximately parallel lithologic time markers. The Chester paleotopographic surface has caused local thick sand deposits with good porosity to strike north-south along the paleovalleys; thinner accumulations occur above the paleodivides. Persimmon Creek field is a small stratigraphic-trap accumulation that occurs above a prominent southward-plunging nose or paleotopographic high on the Chester limestone surface. Morrow sandstone prospects can be defined by locating the most likely sites of thick porous sand accumulation controlled by Chester paleotopography.--Modified journal abstract.