Connecting Hydraulic Fracture Deformation to Microseismicity

In order to characterize the deformation associated with the stimulation of a hydraulic fracture, we use a cluster-based approach to describing microseismic events, their temporal and spatial inter-relationships, and their source parameters. With a case study in the Permian Basin, we show how the clusters of seismicity associated with the completion of a horizontal well differentiate into two categories on the basis of their dynamic parameters. Spatially, the first grouping shows tight locations around a presumed zone of primary stimulation and near the treatment well, the second grouping is more diffuse and outside of this first group. As such we interpret these groupings as giving a first-order sensitivity to fluid (Group 1) and stress (Group 2) interactions, inferring that we can resolve structure within a microseismic event cloud to distinguish the degree of deformation and therefore future productivity of the volume containing the seismicity. We suggest that using this first grouping to infer the region of primary production will allow us to be more circumspect in estimates of stimulated volume, therefore offering a path to reconcile large estimates of stimulated volume based only on event locations and inferred volumes from rate-transient analysis.