Factors Controlling Static to Dynamic Empirical Relationships in Marginal Marine Clastics

Static elastic properties are derived from measuring the volumetric strain for a given stress. However, dynamic elastic properties are measured from primary and secondary wave velocity and density. In a petroleum system of discontinuous sandstone reservoir packages, the top seal layer consists of siltstone with marginal marine shale. The reservoir packages contain different types of fluid. One explanation is having different elastic properties of the seal that allow for fluid migration from the reservoir. One of the elastic parameters that are studied for the seal layer is Young’s Modulus. This is derived from the well logs resulting in dynamic measurements. Also, Young’s Modulus is measured in the lab by straining core plugs. The static and dynamic measurements show inconsistent discrepancy. Many factors can be the source of discrepancies between the static and dynamic measurements including depth, bulk volume, grain density, dry weight, grain volume and porosity.