I watched a fascinating and worrying report on channel4 this week on gas extraction and earthquakes, in of all places Holland. The first really major hydrocarbon finds in Western Europe post WWII were made in Holland. I remember studying it in my O-level geography. Unlike the north sea these finds were largely on land. The finds (and these were big fields) stimulated North Sea exploration. The fields were centred on Groningen and came on stream in the early sixties. The following graph shows the output over the years (source BP statistical review of world energy).
The problem the Dutch have found is one of earthquakes. Its become such a serious problem that the Dutch government are forcing production to cease (albeit gradually). There has clearly been a huge scandal with up to 8 billion euros of damage. Many people are waiting for compensation and have had to move out of their homes but it also includes public buildings. Channel4 showed at least one school closed with the pupils having to use huts. (Its so bad they showed an earthquake drill in a school).
So what has gas extraction and earthquakes to do with us in the UK? Well the government has allowed fracking to go ahead in England. So far amid huge public opposition (increasingly from Tory MP’s in rural areas as well) its going ahead at just one site in Lancashire. It been stopped about 6 time due to earthquakes. These are very minor, but the threshold has been set much lower than in Holland where it was set at 4 on the Richter scale.
It does seem that oil and gas extraction causes earthquakes on a regular basis. At my children’s school there was a British geological survey map on the wall. This showed the distribution of earthquakes over the UK. What was interesting was the great majority were in the part of the north sea where the oil and gas fields were. All this has been invisible due to the minor tremors being out at sea. In the UK there is tiny amount of onshore oil and gas up until now. The Dutch set their levels where there is said to be no damage to buildings, but clearly there has been a huge issue. Albeit one that I missed when we were on holiday in Holland.
The geology is different in Holland from the UK being sandstone and its conventional gas. However we are running a huge fracking experiment. There is pressure on the government to liberalise both the planning and earthquake levels (with levels set so low it simply cannot be economic). We cannot know what will happen if fracking really takes off and could be struck with huge problems if we do since clearly earthquakes down the Richter scale clearly cause significant damage.