Analysis of B Value from Barnett Shale Microseismic Data

In 2010, ConocoPhillips acquired microseismic data targeting the Barnett shale from Stocker field in Texas, USA. Two horizontal wells were fractured in eighteen stages. More than 7,000 microseismic events were located using two down-hole receiver arrays. The b values were calculated using the magnitude distribution of the events in each stage by maximum likelihood methods. This work analyzed the temporal and spatial variations of b values in every simulation stage. We showed (1) that the spatial variation of the b value may help to delineate reservoir heterogeneity and (2) that the temporal variation of the b value in each stage may be related to the mechanism of fracture growth.