Pressure monitoring in tight gas exploration and production with multicomponent seismic data

Tests were carried out by the Reservoir Characterization Project (RCP) of the Colorado School of Mines at Rulison Field, Colorado, to see if time-lapse (4D), multicomponent seismic data could aid in detecting pressure depletion in a tight gas field. Calibration occurred through zonal pressure testing, acquisition of three 9C seismic surveys, specialized image and cross-dipole logging, and microseismic monitoring. Calibration indicated that pressure drops of a few hundred psi could be detected and monitored from surface seismic data. By monitoring pressure depletion, drainage area or sweep can be assessed from 4D multicomponent seismic data, thereby enabling the technology to improve recovery efficiency in tight-gas development. In addition, time-lapse data can potentially be used to locate fractures and design frac jobs to provide greater wellbore deliverability, higher Expected Ultimate Recovery (EUR) and improved economic recovery. Rulison Field was chosen as the site for RCP’s Phases X and XI reservoir characterization research.