Microseismic Monitoring of a Fractured Reservoir in Oman Undergoing Steam Injection

S.S. Busaidi¹, S. Mahrooqi¹, F. Clow¹, O. Harrasi¹, T. Urbancic², and A. Baig²

Abstract

A microseismic network was installed over a fractured heavy oilfield in Oman. The multi-array microseismic network was designed for long term monitoring of cap rock integrity, tracking steam chamber progression, identifying both fault creation/reactivation and possibly any local state of stress. More than 3,300 microseismic events have been located from April, 2011 to May, 2013. In addition to the basic processes of locating the events, interpreting those locations relative to the picked faults, correlating the microseismic event rate with steam injection rate, temperature rise and oil production, advanced processing can reveal much more information contained within the microseismic records. The adequate spatial coverage of this microseismic network allows Source Moment Tensor Inversion (SMTI). The SMTI provides valuable insight on how the rocks are deforming, failure mode mechanisms (opening, closing, sliding or tearing mechanism), and the orientation of the individual fracture in terms of their strike and slip direction and the stress-strain direction, from which we can identify a global stress regime and any local stress anomalies.

AAPG Search and Discovery Article #90188 ©GEO-2014, 11th Middle East Geosciences Conference and Exhibition, 10-12 March 2014, Manama, Bahrain