Sequence-stratigraphic analysis of Jurassic and Cretaceous strata and petroleum exploration in the central and eastern Gulf coastal plain, United States

Abstract

The formulation of an integrated sequence-stratigraphic and biostratigraphic framework is fundamental in the design of an effective strategy for petroleum exploration in a sedimentary basin. For the interior salt basins of the Gulf coastal plain of the United States that are filled primarily with Mesozoic postrift nonmarine to marine siliciclastic and carbonate deposits, a sequence-stratigraphic approach using transgressive-regressive (T-R) sequences and integrated with biostratigraphic information has utility as a method for establishing such a framework. The sequence stratigraphy established for Upper Jurassic and Cretaceous strata is used to categorize petroleum reservoirs in the central and eastern Gulf coastal plain. Transgressive aggrading eolian, fluvial, and coastal sandstone facies of the T-R sequences include highly productive hydrocarbon reservoirs in the eastern Gulf coastal plain. Productive reservoirs in the central and eastern Gulf coastal plain include regressive infilling fluvial to nearshore marine sandstone facies, and nearshore marine, shelf, ramp, and reef carbonate facies. Transgressive backstepping nearshore marine facies include highly productive reservoirs in the central Gulf coastal plain. These transgressive and regressive facies are recognized by their wireline log patterns and seismic reflection configurations. Knowledge of the diagnostic wireline log signatures and seismic reflection characteristics assists in the detection of exploration targets.