3D seismic interpretation and fault slip potential analysis from hydraulic fracturing in the Bowland Shale, UK

The Bowland Shale Formation is one of the most promising targets for unconventional exploration in United Kingdom, with estimated resources large enough to supply country's entire natural gas consumption 50 years. However, development has stalled due concerns over hydraulic-fracturing induced seismicity. Only three wells have been drilled and hydraulic fractured date Shale, all produced levels seismicity sufficient magnitude be felt at surface. Susceptibility will determined by presence critically-stressed faults. such faults can go undetected conventional interpretation 2D or 3D seismic surveys if they are shorter that resolution retrievable from a survey, low (and some cases even zero) vertical displacement. In cases, cause may only visible via microseismic observations once reactivated. To better identify fault planes images, their reactivation potential fracturing, high-resolution fault-detection attribute was tested survey acquired Preston New Road site, where two shale-gas were hydraulic-fractured 2018 2019, obtaining lengths between 400 1500 meters. Fault slip then integrating obtained formation's stress pore pressure conditions (with shale also being significantly overpressured), several critically stressed identified near previously wells. largest events approximately 200 meters length magnitudes below 3.0 (as imaged multicomponent, downhole monitoring array deployed during fracturing stimulations), could not mapped larger than length.