Print this pageNumeric Stratigraphic Modeling of a Gulf of Mexico Plio-Pleistocene Depocenter: Testing Sequence Stratigraphic Concepts using a High Resolution Geologic Example
ARMENTROUT, JOHN M., LINDA S. SMITH-ROUCH, and SCOTT A. BOWMAN
Numeric simulations based on integrated data sets enhance our understanding of depositional geometry and facilitate quantification of depositional processes. Numeric values constrained by high-resolution geologic data sets can be used in modeling iterations testing each variable, and in predicting lithofacies distributions under various depositional scenarios using the principles of sequence stratigraphic analysis. Modeling variations can include depositional geometry and lithofacies distributions between a different tectonic settings (passive versus active margin) and climate regimes (hothouse versus icehouse). Once a geologically plausible model is constructed it can be used to model, test, and predict the occurrence of organic-rich rock, reservoir rock and sealing rock, and to model maturation A timing, potential migration pathways and timing of trap formation.
A high-resolution data set from the Pliocene-Pleistocene siliciclastic system in the Gulf of Mexico, consisting of wells integrated with a regional seismic grid, is used to illustrate such variations. Numeric simulations result in geometry and facies distributions consistent with those interpreted using the integrated stratigraphic analysis of the calibrated seismic profiles. An exception occurs where the simulated sediment thickness and percent sand from 3.8 to 1.6 Ma within an upper slope minibasin was less than that mapped using a regional seismic grid. Regional depositional patterns demonstrate that this extra sand-prone thickness was sourced from out of the plane of the modeled transect, illustrating the necessity for three dimensional constraints on two dimensional modeling.