Abstract by Joseph Phillips
Building a Predictive Model for Stratigraphic Transitions and Lateral Facies Changes in the Cretaceous Almond Formation, Wyoming
The Almond Formation, located in the Greater Green River Basin, records deposition of coastal plain and shallow marine facies in a net-transgressive sequence along the western margin of the Cretaceous Interior Seaway. The aim of this research is to build a predictive model of lateral and temporal facies transitions across the basin. Measured sections on the east side of the basin show coastal plain facies giving way to shallow marine facies, although well log and core analysis illustrate that over two hundred feet of shallow marine cycles are not preserved in outcrop. Core and outcrop analysis reveal stacking patterns interrupted by frequent progradational pulses that involve bayfill sediments within shallow marine cycles. This indicates the presence of a lagoonal depositional environment that perhaps pervaded to the west as shorelines retreated. Along the eastern side of the basin, marine parasequences are thicker at the base, and thin upwards. Coastal plain facies to the west follow a similar trend and could help to connect a chronostratigraphic framework across the basin as well as lead to a better understanding of sediment partitioning and preservation.