Benefits of the Dense Seismological Station Network in Groningen. Speaker Jesper Spetzler, KNMI

The station network in Groningen has in the last year been significantly improved. Currently, the network consists of about 80 station locations covering most of the province of Groningen and with a few stations further away. Each new station location has the same instrument configuration that is 4 geophones in a 200 m deep well and an accelerometer at the surface. Places with stations are only separated by 3-4 kilometers. Data from the stations are send directly to the KNMI. New events are automatically detected, located and published on the KNMI webpage.

Recorded data from the new dense network have helped to improve the location estimation of induced earthquakes. The hazard model for Groningen has been refined with the help of accelerometer measurements. One important aspect in the hazard model is the amplification of seismic waves due to shallow geology. The geophysical properties of the shallow subsurface and much deeper subsurface are being probed with new recorded data.

I will show results of the improved hypocenter location of induced earthquakes, discuss the latest development in the hazard model of Groningen and give examples of the estimation of near-surface properties.