In ‘Fracking’ shale and US ‘peak gas’ (EPN of 1 July 2010) I drew attention to the relief being offered to dwindling US self-sufficiency in natural gas by new drilling and subsurface rock-fracturing technologies that opens access to extremely ‘tight’ carbonaceous shale and the gas it contains. The item also hinted at the down-side of shale-gas. The ‘fracking’ industry has grown at an alarming rate in the USA, now supplying more than 20% of US demand for gas. This side of the Atlantic the once vast reserves of North Sea gas fields are approaching exhaustion. This is at a time when commitments to reducing carbon emissions dramatically depend to a large extent on hydrocarbon gas supplanting coal to generate electricity, releasing much lower CO2 by burning hydrogen-rich gases such as methane (CH4) than by using coal that contains mainly carbon. Without alternative, indigenous supplies declining gas reserves in Western Europe also seem likely to enforce dependency on piped gas from Russia or shipment of liquefied petroleum gas from those major oil fields that produce it. The scene has been set in Europe in general and Britain in particular for a massive round of exploration aimed at alternative gas sources beneath dry land. Unlike the US and Canada, the British are not accustomed to on-shore drilling rigs, seismic exploration and production platforms, and nor are most Europeans. Least welcome are the potential environmental and social hazards that have been associated with the US fracking industry, which seem a greater threat in more densely populated Europe.
The offshore oil and gas of the North Sea fields formed by a process of slow geothermal heating of solid hydrocarbons or kerogen in source rocks at a variety of stratigraphic levels, escape into surrounding rocks of the gases and liquids produced by this maturation, and their eventual migration and accumulation in geological traps. By no means all products of maturation leave shale source rocks because of their very low permeability. That residue may be much more voluminous than petroleum liquids and gases in conventional reservoir rocks; hence the attraction of fracking carbonaceous shales. British on-shore geology is bulging with them, particularly Devonian and Carboniferous lacustrine mudstones, Carboniferous and Jurassic coals, and the marine black shales of the Jurassic (see http://www.bgs.ac.uk/research/energy/shaleGas.html and https://www.og.decc.gov.uk/upstream/licensing/shalegas.pdf), to the extent that areas of potential fracking cover around a third of England, Wales and southern Scotland.
News is breaking of a major shale-gas discovery beneath Blackpool, the seaside resort ‘noted for fresh air and fun, where Mr and Mrs Ramsbottom went with Young Albert their son…’ (Albert poked a stick at Wallace the lion and was eaten), said by energy firm Cuadrilla to have gas reserves of 5.7 trillion m3. The announcement followed 6 months of exploratory drilling, and drew attention to the burgeoning interest by entrepreneurs in the upcoming 14th Onshore Licensing Round for petroleum exploration in Britain. It isn’t just from major petroleum companies, but in some cases even what amount to family businesses finding sufficient venture capital to spud wells; similar in many respects to the US fracking boom that began a mere 10 years ago.
- Deep under Lancashire, a huge gas find that could lead to 800 ‘fracking’ wells (independent.co.uk)
- Fracking gas test drill discussed (bbc.co.uk)
- Is fracking environmentally friendly? (environmenteng.wordpress.com)
- The answer to cheaper gas bills? (bbc.co.uk)
- Camp Frack mobilises against UK’s first shale gas well (guardian.co.uk)