资源环境科技发展态势分析平台

The OGA has published a series of commissioned reports on induced seismicity. BGS seismologists Brian Baptie and Margarita Segou were co-authors of one of these report entitled 'Statistical Modelling of the Preston New Road Seismicity: Towards Probabilistic Forecasting Tools' together with Simone Mancini (Bristol University/BGS) and Max Werner from Bristol University.

The report looks at research into the feasibility of statistically forecasting the microseismicity observed during and after hydraulic fracturing for shale gas. We used a statistical model that was originally developed for tectonic seismicity, called an epidemic type aftershock sequence (ETAS) model, which has been widely applied for forecasting tectonic earthquake sequences. It has also been used with some success for induced seismicity.

The model parameters were determined using data recorded during hydraulic fracturing unconventional shale gas exploration in 2018 by Cuadrilla Resources at its Preston New Road site near Blackpool, consisting of over 38 000 microseismic events. We find that the performance of the model forecasts is mixed, performing well during periods of low to moderate seismicity but under-predicting during the most active periods. This mixed performance may be a result of features in the induced seismicity that are rare in natural seismicity. For example, the induced events do not appear to show the same magnitude-dependent triggering and clustering observed in natural seismicity. This suggests that further research is required to develop the models and to test them on independent datasets such as the data recorded during operations at the PNR2 well, which was hydraulically fractured between August and October 2019.