“To me at least the connection is clear and statistically certain… far more certain than anything I ever see in the stock market or the economy.”

That’s Jeremy Grantham, the highly-regarded co-founder of the $117 billion investment fund GMO, who predicted both the dot com crash of the late 1990s and the subprime meltdown a few years later. Above is an accompanying chart included in his latest investment letter.

Rather than pushing an investment idea here, he’s convinced there’s a causal link between a surge in earthquakes measuring above 3 on the richter scale in the US and the boom in hydraulic fracturing (“fracking”), the controversial drilling technique used to extract oil and gas from shale rock.

via One of the world’s great investment thinkers is convinced fracking is causing earthquakes – Quartz.