Jurassic shales of the Weald Basin: geology and resource estimation

Robert Gatliff (BGS)Director Energy & Marine GeosciencePresenting on behalf of the BGS-DECC team

Area studied

Area already has conventional hydrocarbons

Green = oil fields; red = gas fields Yellow = currently licensed

How BGS calculated the shale resource in the Weald

• Wells (oil/gas and other types) to identify the tops and bottoms of the main shale layers (of which 5)

• Seismic sections to map rock layers in subsurface• 3D computer model to estimate the volume of shale• Studies of the burial and uplift history & of the

organic content of the shale to narrow down the layers and areas that might yield hydrocarbons

Wells studied

Black = key wells; blue = other wells

Seismic

Area prospective for shale oil

Estimate of oil in-place• 2.20 – 8.57 billion bbl (293 – 1,143 billion

tonnes) (P90 – P10)• This is an in-place resource not a reserve• Drilling and testing of new wells is required to

confirm this model especially in areas of poor well control, and to assess the feasibility of production

Where to get more

informationwww.gov.uk/oil-and-gas-onshore-exploration-and-production

www.bgs.ac.uk/shalegas