Multi-channel waveform clustering: a first look at microseismic multiplets from coalbed methane stimulation

Abstract

Interpreting microseismic events triggered by reservoir stimulation (especially hydraulic fracturing) has become a common practice to understand fracture dimension and geometry. In this area of study, the need for accuracy and resolution of microseismic data is relatively high since the object of investigation is relatively small compared to other seismological studies. Hence, a robust tool is necessary to assure the quality of microseismic event locations and support the interpretation. To achieve these primary objectives, we performed a waveform clustering workflow that analyzes all waveforms representing a microseismic event. Using this approach, we identified multiplets suggesting events that are closely located and originated from the same source mechanism. We tested the workflow on microseismic data from coalbed methane stimulation. The method increases our confident on using the dataset for interpretation especially since the monitoring survey is limited by a single borehole array with very minimal spatial coverage.