Microseismic monitoring for fracturing in the Colorado Shales above a thermal oil recovery operation

A microseismic monitoring system has been developed for the purpose of identifying induced fracturing in the Colorado Shales above a thermal oil recovery operation located at Cold Lake, Alberta, Canada. The system is an extension of continuous monitoring systems employed in mines [e.g. Gibowicz & Kijko 1994, Talebi et al. 1994] and builds on many of the learnings from oil field applications where the azimuth and extent of hydraulic fractures have been mapped with similar systems [e.g. Talebi et al. 1994, Warpinski et al. 1997]. The primary application of the system described herein is to identify and prevent casing or well failures. This objective can be achieved by observing and interpreting the events associated with (i) a fluid release and induced fracturing, (ii) movements in the rock that can lead to casing damage and failure, and (iii) the actual breaking of a casing. That latter represents a novel application of microseismic monitoring and has been supported by theoretical developments and field observations.