Earthquakes in the Netherlands

 Hello everyone!

As I mentioned last week, there is a region to the southwest of the Netherlands that has notable earthquake activity, which I thought may affect the country on a smaller scale. However, according to ThinkHazard.org, earthquake hazards are classified as a medium-level concern in the Netherlands. As seen in the map below, earthquakes are most prevalent in the southeastern regions of the Netherlands.




The Royal Netherlands Meteorological Institute (also known as KNMI) has been measuring the country’s earthquakes since 1904. The strongest earthquake KNMI has on record dates back to April 13 of 1992 and measured 5.8 on the Richter scale. The epicenter was located several kilometers southwest of Roermond, which experienced significant damage, along with Maaseik and Heinsberg. The total damage was estimated to have cost the Netherlands 275 million guilders (approx. $150 million USD). This earthquake was also felt in the Czech Republic, Switzerland, France and England.


At the Brunssummerheide, shearing occurred along wooded slopes. As a result of the seismic vibrations, the stability of the water-saturated sandy bottom was lost.


According to KNMI, earthquakes in the Northern Netherlands are induced by gas extraction sites. The first induced earthquake that occurred in the North took place on December 26, 1986 in Assen. Gas reservoirs located in Groningen, Drenthe, Friesland, and North Holland also experience induced earthquakes. Groningen, which is the largest of the Netherlands' gas fields, experienced a total of 72 earthquakes in 2021, 69 in 2020, and 85 in 2019. As seen in the chart below, most of these earthquakes did not reach about 1.5 in the Richter scale.


Annual number of earthquakes in the Groningen gas field with a magnitude of 1.5 or higher from 1991 to 2022. ©KNMI


The KNMI has established a risk-reduction-cycle that includes making possible atmospheric or seismic risks known to risk managers and the public, warning and supporting the public when incidents arise, then analyzing the severity of the incident and working towards improvement. The exact steps one is to follow in the case of an earthquake are not directly mentioned on the KNMI’s site or resources; however, the European Facilities for Earthquake Hazard and Risk (EFEHR) provide clear instructions. When inside a building, EFEHR advises people to take cover, beware of falling objects, keep away from windows and glass walls, and only leave the building when the surrounding area is safe. When outside, stay outside, keep away from buildings, bridges, electricity pylons, large trees, and other things that could collapse or fall, and keep away from the shores or bodies of water after strong shaking.


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