'Fraking' has caused earth quakes in the uk, where they are trying to extract the gas down there. https://en.wikipedia.org/wiki/Hydraulic_fracturing https://en.

'Fraking' has caused earth quakes in the uk, where they are trying to extract the gas down there. https://en.wikipedia.org/wiki/Hydraulic_fracturing https://en.wikipedia.org/wiki/Hydraulic_fracturing But that is a slightly different thing to geothermal drilling. You're basically drilling 4km down, and putting a big pipe in. Then you run water through it, which heats the water. There have been no earth quakes caused in Australian drilling for geo thermal plants to my knowledge. However, it depends on the technology used. Some of these people are just dumping massive amounts of toxic chemicals and blasting the crap out of the rocks. Obviously this affects the water down there - and is super evil. If you're careful, and with planning I don't see why it wouldn't be possible to do safely and in a non toxic way.