Using Advanced Logging Measurements to Develop a Robust Petrophysical Model for the Bakken Petroleum System

摘要

The Bakken petroleum system (BPS) can be considered a hybrid play because it is composed of both conventional and unconventional elements. The conventional aspects include the presence of separate reservoir intervals (Scallion, Middle Bakken, Sanish and Three Forks) and source-rock intervals (Lower Bakken and Upper Bakken shales) along with more problematic intervals (Basal Bakken). This is in direct contrast to most unconventional shale plays, in which a single lithologic or stratigraphic interval comprises both the source rock and the reservoir. The unconventional aspects of the BPS include very low permeability conventional reservoir sections and combined shale -rich source and reservoir intervals. Additional complexity results from stacked depositional environments with significant variations in lithofacies, mineralogy, total organic carbon (TOC), and rock textures ranging from highly bioturbated to finely laminated.