Unconventional Approaches for an Unconventional Faulted Reservoir - From Target Selection to Post-stimulation Analysis

Most microseismic monitoring of hydraulic fractures entails determination of the event locations and magnitudes. This “first-order” analysis has been very successful in determine fracture trends and sizes but is limited approach. We illustrate a number of examples of how higher-order seismic moment tensor inversion (SMTI)analysis can provide more detailed answers to questions in the fracture engineering community. Determination of the fracture planes from the SMTI data shows the development of an interconnected fracture network that provides conduits for the treatment fluids into formation. From here, the spatial variation of opening and closure modes of the moment tensors yields a map of the regions of the treatment zone where permeability has been enhanced by the opening of fractures. That this region of enhancement does not simply form an envelope around the microseismic events has important implications for the ideas of stimulated reservoir volume. Finally, we show how temporal analysis of the SMTI data together with the treatment parameters can be used to determine where the fracture treatment has reached points of diminishing returns, where further treatment does not enhance the permeability of the reservoir. This final type of analysis can be used to optimize future fracture treatments.