Maximum flooding surfaces and sequence boundaries: Comparisons between observations and orbital forcing in the Cretaceous and Jurassic (65-190 Ma)

Abstract

We have undertaken a simplified calculation of orbital forcing back through the Cretaceous to the Late to Middle Jurassic from 65 to 190 Ma. So long as the Earth has a continental ice volume, orbital forcing will impose a 400-ky periodicity upon glacioeustasy and thereby on fourth-order sequence stratigraphy cycles. Similarly, third-order cycles were defined by orbital forcing of 2.4 ∓ 0.4 my (predominately 2.0- and 2.8-my cycles). These concepts greatly simplified the task of unraveling sequence stratigraphy. Our sea-level calculations are comparable with stratigraphic observations and the results are consistent with a persistent continental ice volume throughout the Late to Middle Jurassic and Cretaceous. In general, they compare well with the Arabian Plate Maximum Flooding Surfaces and the Cretaceous and Jurassic stage boundaries, within the limits of the recognized stratigraphic time scales. We used simple Parametric Forward Models (PFMs) for modeling changes in sea level, subsidence, and sedimentation and noted that PFMs can be applied to other tasks. The results will provide for rapid, cost-effective forward modeling on tasks such as reservoir characterization and flow simulation.