Fig. 5From: Multi-channel waveform clustering: a first look at microseismic multiplets from coalbed methane stimulationIdentified multiplet groups in a map view suggesting two orientations for hydraulic fracturing: primarily N330° and secondarily N240° (a). A vertical section in South–North projection showing the triggered microseismic events is mostly located in the coal zone of injection indicated by red star (b). Horizontal dash lines are coal thickness at the injection wellBack to article page