ESE on Shale Gas

In February the department was The first organisation summoned to give evidence to the UK government's Energy & Climate Change Select Committee shale gas inquiry.

In February the department was the first organisation summoned to give evidence to the UK government's Energy & Climate Change Select Committee shale gas inquiry.  Research by the Geology Department some 25 years ago identified favourable areas for shale gas resources in the Jurassic shales of the Weald and Lower Carboniferous shales of the Midlands.

Shale gas is natural gas produced by friable, organic-rich mud rocks known as shales. It is considered an unconventional source of natural gas, since unlike many other sources, shale has a very low permeability and gas is not easily able to flow and escape from the rock.

Extracting shale gas from a source involves first finding source shales with high enough organic contents to generate sufficient gas, and which are sufficiently rigid and brittle to fracture to allow the gas to be extracted. Methods of extracting shale gas involve hydraulic fracturing, in which high pressure water is used to fracture the shale around the borehole. Often it is also necessary to drill horizontal boreholes to extract sufficient gas.

Shale gas has become important in the USA over the last decade and provides an important alternative to traditional gas sources in providing energy. Opinion is divided over whether shale gas will reduce greenhouse gas emissions since it produces more methane, a potent greenhouse gas, than conventional gas sources. Difficulties in extraction and minimising environmental impact, however, are engineering challenges that apply to all natural hydrocarbon sources and highlight the need for investment in engineering research if future energy production is to be secured.

A drilling programme in the Cheshire Basin is now under way to test technology and search for shale gas resources. A further presentation on the department’s research on UK shale gas resources will be given to the All-Party Parliamentary Group for Earth Sciences in March.