Abstract

Enhanced geothermal systems can provide a substantial share of the global energy demand if certain hurdles are overcome. One such hurdle is the accurate imaging of the fracture networks created in subsurface through hydraulic stimulation of these systems. Microseismicity associated with the stimulation is the primary means to locate the event hypocenters for estimating the stimulated rock volume. Using the data from a single three-component accelerometer in a monitoring well, the polarization features viz. azimuth, incidence, rectilinearity, and planarity are used as inputs for the unsupervised manifold approximation followed by clustering. We show that density-based clusters in the projected 3D space correspond to distinct types of hydraulically fractured zones around the injection point, thereby refining the interpretation of the microseismic cloud. The temporal evolution of these clusters can be used to track fracture creation and propagation for the various types of fracture zones.