Sequence stratigraphic evaluation of the Prue Sandstone in Creek County, Oklahoma

Abstract

The Prue Sandstone is studied extensively across northeastern Oklahoma and Kansas. Previous studies concluded the Prue Sandstone was deposited in a southerly prograding fluvial-deltaic complex with distributary channels and incised valleys. However, the Prue Sandstone is not studied extensively in Creek County, Oklahoma. Also, recent advancements in sequence stratigraphy caused reinterpretation of the Prue Sandstone and support hypotheses that the Prue sediments are estuarine, tidal to fluvial dominated. A combination of regional cross-sections, structure maps, and isopach maps were used to evaluate the regional structure, depositional environments, and sandstone distribution. The depositional paleo dip during Prue time was northwest to southeast. The Prue interval isopach and net isolith maps show that most sand deposition occurred where the interval was thicker in a marine embayment in this area. Core facies determined from 5 wells were described and used to interpret depositional environments. The sandstones in these cores all show tidal influence. Thin section petrographs determine the sandstones are litharenites, with an abundance of quartz and metamorphic rock fragments. The Prue was initially deposited in a tide-dominated, progradational delta that trends west to east across the study area. When the sea level declined, channels incised the delta generating an incised valley complex that may have followed older distributary channels. During subsequent sea level rise, estuaries formed, sediments were reworked, and the channels back filled. A late stage tidal channel eroded the incised valley complex, contributing to lateral discontinuity in reservoirs.