A recently developed quantitative model predicts the stratigraphy and geometry of foreland basins and passive margin basins in response to deformation history and sea-level change. The model combines a largely-accepted mechanical description of the lithosphere with a new approach, that of simulation of the surface transport of sediments by diffusion. The robustness of the new approach will be tested by comparing the predicted stratigraphies of two foreland basins, the colville basin and the Western Interior Seaway, to the geological data. Sediment fluxes and depositional profiles will be measured over known time intervals and the lithospheric loads calculated by two-dimensional back-stripping procedures. The load histories and sediment fluxes will then be input to the forward model of basin evolution. The project is a collaboration of scientists from Cornell University, Lamont-Doherty Geological Observatory, and the University of Colorado. The results will resolve whether or not the lithosphere relaxes significantly during foreland basin formation, the tectonic effects of thrusting on subsidence in the distal parts of basins, and the contribution of eustatic sea-level change to stratigraphic sequences. These findings will have important consequences for tectonics and sedimentology.
