Science Questions

Will removing oil destabilise the Earth? Michael

Chris - The answer we trot out is the oil volume relative to the crust of the Earth is very minor. Situations like this highlight the fact that there can be consequences.

Richard - This is something that happens probably a few times a year around the world. What’s happened here has been unfortunate in that the area was ready for a mud volcano before. In other words geologically the conditions were suitable. Unfortunately this company drilled a well which had operational problems which provided the pipe work, the plumbing so that the mud volcano would form. This is something that happens a handful of time each year. This is the worst case in that unfortunately it happened in a populated area and it brought a lot of mud with it.

Chris - People are probably going to be quite surprised to learn that we do have one of these in Britain although, thankfully, not on the scale of the Indonesian example.

Richard - Yes. It is nowhere near on the scale of the Indonesian example and it is a natural occurrence. These are very small mud volcanoes outside Swindon but what I like about them is they provide an analogue for what’s happening in Java right now. It’s actually a limestone, a Corallian which is a Jurassic aged limestone: 150-160 million years old. It’s supplying fluid and the fluid is then passing through a clay called the ampthill clay and the clay is brought to the surface. It actually has with it a number of beautifully preserved ammonites.

Chris: That saves fossil hunters a bit of effort. Richard, thank you very much.

June 2008