Earthquakes — once culturally and legally dubbed an “act of God” — are now set off by humans. Fracking, drilling and wastewater disposal can trigger these tremors, but just how common are these events?
A new database, created by geophysicists at Durham and Newcastle Universities in the United Kingdom, has tracked down 730 cases of man-made earthquakes over the last 150 years. The Human-Induced Earthquake Database (HiQuake) is the most comprehensive collection of these quakes to date and might be used to predict future ones.
“Although incomplete, HiQuake provides a more global picture than people have had access to before,” Miles Wilson, a Durham geophysicist and the study’s lead author, said via email. “Humans are increasingly making changes to the Earth to meet greater resource demands, which is why it’s so important to understand the effects these changes might have.”
Wilson and his colleagues began developing the database in 2016 with support from the Dutch oil and gas company Nederlandse Aardolie Maatschappij (NAM). NAM operates one of the largest gas fields in the world — the Netherlands’ Groningen gas field — where the company’s gas extraction work caused a magnitude 3.6 earthquake in 2012.
For Huizinge, a local village on the outskirts of Groningen, this was the largest induced earthquake they ever felt. In their report, published in Seismological Research Letters, the researchers noted that the company contacted them in order to find a way to inform the public and resource-extraction industries of earthquake risks. PBS NewsHour contacted NAM multiple times, but they did not provide a comment.
The team combed through academic papers, media coverage, government records and industry documents to find as many reports of human-caused earthquakes as possible. The documented incidents dated as far back as 150 years, and many of the tremors were between magnitude 3 and 4.
Mining was the most common quake-trigger, accounting for 37 percent of human-made cases. Water contained behind reservoir dams made up 23 percent of these events, while conventional oil and gas extraction caused 15 percent.