A Chronostratigraphic Assessment of the Pronghorn Member of the Bakken Petroleum Syste

Chronostratigraphic definition of the Pronghorn Member of the Bakken Petroleum System facilitates correlation both within the Williston Basin and to coeval formations in adjacent basins. Palynological analysis of the Pronghorn Member reveals parasequences, depositional environments, and relative age. The Pronghorn Member consists of a discrete depositional sequence, variably preserved throughout the basin although locally complete.;Three palynofacies were established within the Pronghorn Member, corresponding to an open marine Lowstand Systems Tract, an intermediate marine Transgressive Systems Tract to Highstand Systems Tract, and a restricted marine Falling Stage Systems Tract. This palynological assemblage corresponds to the palynozone VCo.;Pronghorn Member microfossil and macrofossil assemblages are similar to those of the Trident Member of the Three Forks Formation in Western Montana and suggest synchronous deposition of the two formations. Considering that the Bakken Formation occurs only in the subsurface, establishing an outcropping analog improves reservoir characterization.