Earthquakes close to natural gas drilling sites in Groningen in northern Netherlands have apparently become more frequent and more intense. An official study published on January 25 estimates that the quakes could reach 4 or 5 degrees on the Richter scale.

The state mining monitoring authority has recommended a reduction in the amount of drilling. On a visit to the region, the Minister for Economic Affairs took the view that this would be “irresponsible from an economic point of view”. In 2011, the gas field generated revenues of €11.5 billion for the state, and it currently supplies gas for 97% of Dutch homes.