Natalia V. Zakharova and David S. Goldberg
Induced seismicity due to pore pressure increase presents a significant risk for carbon sequestration in fractured formations. In order to evaluate fracture stability, detailed knowledge of the in situ stress is required. High-resolution wellbore images allow identifying both natural discontinuities and drilling-induced failures indicative of the in situ stress regime. This study demonstrates an application of borehole techniques for stress analysis at a potential CO2-storage site in the Newark Rift basin in the northeastern U.S (TriCarb project). Effects of borehole deviation on wellbore failure and constraints on complete stress field have been determined. Stability of natural fractures at various depths was evaluated for a range of potential stress profiles. Preliminary analysis suggests that a significant capacity for pore pressure increase without fracture reactivation exists in deeper reservoirs, but additional in situ test data are needed for a more complete assessment of the induced seismic risk from potential CO2 injection in the region.
Zakharova, N. V., D. S. Goldberg, and D. Collins (2013), In-Situ Stress Constraints from Borehole Data in the Context of CO2-Storage Site Characterization, Proceedings of the 47th US Rock Mechanics/Geomechanics Symposium, 23-26 June 2013, San Francisco, California, USA.
Goldberg, D. S., T. Lupo, M. Caputi, C. Barton, and L. Seeber (2003), Stress regimes in the Newark basin rift: evidence from core and downhole data, The great rift valleys of Pangea in eastern North America, 1, 104-117.