Summary
We present a method for visualizing microseismic event distributions using the accumulation of image volumes. The procedure is demonstrated using a synthetic dataset designed to mimic the microseismic event distributions that we have observed during hydraulic fracturing. Our results show that cumulative images provide a potentially useful tool for the investigation and interpretation of event distributions. In particular our results highlight the importance of multicomponent data and S-wave information in constructing source images. The production of cumulative images for individual moment tensor components also allows for the identification and mapping of source mechanisms without computation of point source location.
Such imaging and visualisation methods avoid the unnecessary step of abstracting microseismic event populations as a group of point sources and instead represent the population of events as a multi-dimensional representation of the frac itself, describing frac development in both space, time and mechanism.
