Assessment of Potential Shale Gas Resources in UK Pennine Basin Carboniferous Shales

Andrews, Ian; Harvey, Toni; Andrews, Ian; Smith, Kevin; Smith, Nigel; Vincent, Ceri

Carboniferous organic-rich basin shales are present at outcrop and at depth across much of the Pennine Basin (central UK). These organic-rich shales are known to be important source rocks for the oil and gas found in conventional oil and gas fields in areas including the offshore UK Irish Sea and the onshore UK East Midlands. These thick shale source rocks are now recognised to form a potential shale gas play. Before any exploration had taken place, The UK shale gas industry is in its infancy, with only four shale gas wells drilled as of Q3 2012. The production data from frac tests of the Preese Hall well during 2011 (which was stopped before completion of the fraccing programme following two local earthquakes) remains confidential; however, the operator Cuadrilla has estimated that some 200 tcf of in place gas occurs across their licence within Carboniferous shales. In a separate assessment in 2010, DECC and BGS estimated that, by a simple scaled basin size analogy with similar producing shale gas plays in the USA, the recoverable reserve potential from the Pennine Basin Upper Bowland Shale could be around 4.7 tcf gas.

Our new 2012 DECC/BGS study has followed a more detailed path, including seismic interpretation of the Carboniferous (Bowland Shale, Hodder Mudstone and laterally equivalent shale formations) across the Mississippian component rift basins of the Pennine Basin, along with well log interpretation and correlation, 3-D depth modelling, geochemical analysis, and 2-D thermal maturity basin modelling. These data have been used to assess the distribution of the potential shale gas play and to estimate the potential in place Carboniferous shale gas resource across the UK's Pennine Basin.

AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013