Regional sequence stratigraphic setting and reservoir geology of Morrow incised-valley sandstones (lower Pennsylvanian), eastern Colorado and western Kansas

Integrated Synthesis of the Permian Basin: Data and Models for Recovering Existing and Undiscovered Oil Resources from the Largest Oil-Bearing Basin in the U.S.

“…The juxtaposition of the transgressive systems tract (shales at the base of the Bayhead Delta) on top of the lowstand coarse sands will result in localized and possibly regional compartmentalization of reservoir units when they are stacked in this manner. The well illustrated in figure 12 typifies the downdip facies tract of Bowen and Weimer (2003). Bowen and Weimer (2003) illustrated the cross-sectional architecture of their informal facies tracts within a sequence-stratigraphic and reservoir-quality framework (figs.…”

“…The well illustrated in figure 12 typifies the downdip facies tract of Bowen and Weimer (2003). Bowen and Weimer (2003) illustrated the cross-sectional architecture of their informal facies tracts within a sequence-stratigraphic and reservoir-quality framework (figs. 13, 14).…”

“…In general, the upper Morrow interval is dominated by shallow-marine shales that were deposited on a low-gradient shelf northwest of the Anadarko Basin during relative highstands in sea level (Bowen and Weimer, 2003). Overall depositional environments within the valley fill vary from fluvial (braided to lowsinuosity to high-sinuosity river systems), estuarine, to marine.…”

“…A major flooding surface marks the top of the valley fill. Of key importance is that Bowen and Weimer (2003) note that within their study area individual valley-fill systems can be correlated, mapped, and put in a sequence-stratigraphic context over a large area (for example, single channel system mapped for 283 km). The other key observation in Bowen and Weimer (2003) is the overall extent of facies tract dislocation (~281 km/175 mi) between lowstand and highstand shoreline deposits.…”

“…Figure 12 illustrates the overall upward change of succession from the lowstand systems tract incised valley upward into the overlying transgressive systems tract within a single well (Bowen and Weimer, 2003). The single-well succession illustrates a level of facies discrimination that is only possible using core data, as the wireline log signature for the lowstand and transgressive systems tract will be similar.…”