Structural Integrity of Oil Storage Caverns at a Strategic Petroleum Reserve Site with Highly Heterogeneous Salt and Caprock

摘要

This paper presents computational analyses to evaluate the effects of heterogeneous salt creep properties, com promised caprock mined for sulfur, and pressure loss in an abandoned brine storage cavern, on cavern wellbore and surface struc tures at an underground oil storage facility. These analyses represent a first attempt to combine several complex, non-homogen eous processes in a dome-scale, three-dimensional geomechanical analysis using caverns meshed to measured geometries. The salt dome is characterized by heterogeneous salt properties, and nonuniformly-damaged caprock due to sulfur mining. Separate computational analyses in this report model the weakened caprock and identify a priority list for cavern borehole inspections, attempt to develop a set of salt creep properties from which predicted cavern volume closure matches measured values for individual caverns, and evaluate what effect that a damaged abandoned cavern may have on nearby caverns and their boreholes.