The Carboniferous shales of the Midland Valley of Scotland: geology and resource estimation

Mike Stephenson (BGS)Director of Science and TechnologyPresenting on behalf of the BGS-DECC team

Area studied

Area has a proven hydrocarbon system

How BGS calculated the shale resource in the Midland Valley of Scotland

• Wells (oil/gas and other types) to identify the tops and bottoms of the main shale-bearing intervals

• 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/boreholes studied

Area prospective for shale oil

Area prospective for shale gas

Estimate of oil in-place• 3.2 – 11.2 billion barrels (421 – 1,497 million

tonnes) and a reasonable central estimate is6.0 billion barrels of oil (793 million tonnes)

• This is an in-place resource (oil in the rocks) not a reserve (what might be produced)

• Drilling and testing of new wells is required to assess the feasibility of production

Estimate of gas in-place• 49.4 – 134.6 trillion cubic feet (1.40 – 3.81

trillion cubic metres) and a reasonable central estimate is80.3 trillion cubic feet of gas (2.27 trillion cubic

metres) • This is an in-place resource (gas in the rocks)

not a reserve (what might be produced)• Drilling and testing of new wells is required 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

Slides if needed for questions

Bowland-Hodder822 – 1,329 – 2,281 tcf gas

Weald2.2 – 4.4 – 8.6 billion bbl oil

Midland Valley of Scotland49.4 – 80.3 – 134.6 tcf gas

3.2 – 6.0 – 11.2 billion bbl oil

Historical oil-shale mines

Location of historical shale mines from http://www.scottishshale.co.uk/GazMines/MineMaps/AAMinesField.html

Area prospective for shale oil

Area prospective for shale gas