Subsidence Monitoring in Conjunction with Methane Gas Production in Louisiana (Phase 1, Deep Well Program)

摘要

Ground deformation monitoring arrays installed at deep methane gas wells (Sweet Lake and Gladys McCall wells) in southwestern Louisiana were continued and data were compiled. High quality data were obtained from the instrumentation arrays. These data include elevation changes of the ground surface determined by first-order levelling arrays, tilt of the ground surface measured by tilt meters of high sensitivity, and the location of low-intensity microseismic events detected by a microseismic monitoring network. The relationship among these observations is not clear at present. A temporal coincidence between observed tilt excursions, microseismicity and large pressure reductions in the production and disposal wells is apparent. Heavy rainfall over a brief period also appears to be coincident with some tilt and microseismic events. These relationships will be further investigated in upcoming phases of this ongoing study.