Theory of Paleozoic Oil and Gas Accumulation In the Big Horn Basin, Wyoming

Abstract

A themy of oil and gas accumulation has been developed to account for the relations anong stratigraphy, structure and fluid distribution in the oil fields that produce from Paleozoic reservoirs in the Big Hom basin of Wyoming.This proposed theory related the eormnonoil-water contacts observed in the normal multi-zoned Paleozoic anticlinal fields to height of the oil column, formational thicknesses in the crestal area, and number of Paleozofc formations productive of hydrocarbons in each field.The similar chemical composition of the PaleozQic crude oils, and of the associated formation waters, the vertical density stratification of fluids in the multizoned fields with large oil columns, and some unusual reservoir pi-essurerelationships are cited in support of the concept of a common pool state.