A research team from Virginia Tech, led by Ryan Pollyea, has found that earthquakes 8 kilometres below the earth's surface are increasing in intensity. Published in the journal Nature Communications, the team's work has found that a super-dense liquid called oilfield wastewater is seeping deep into the sheets of the earth, causing massive pressure changes that could be increasing earthquake intensity. Matthew Hall got into contact with Ryan Pollyea and Martin Chapman from Virginia Tech to see what all the rumble is about... Like this podcast? Please help us by supporting the Naked Scientists