资源环境科技发展态势分析平台

Earthquakes induced by natural gas extraction from the Groningen reservoir, the Netherlands, put local communities at risk. Responsible operation of a reservoir whose gas reserves are of strategic importance to the country requires understanding of the link between extraction and earthquakes. We synthesize observations and a model for Groningen seismicity to produce forecasts for felt seismicity (M > 2.5) in the period February 2017 to 2024. Our model accounts for poroelastic earthquake triggering and rupture on the 325 largest reservoir faults, using an ensemble approach to model unknown heterogeneity and replicate earthquake statistics. We calculate probability distributions for key model parameters using a Bayesian method that incorporates the earthquake observations with a nonhomogeneous Poisson process. Our analysis indicates that the Groningen reservoir was not critically stressed prior to the start of production. Epistemic uncertainty and aleatoric uncertainty are incorporated into forecasts for three different future extraction scenarios. The largest expected earthquake was similar for all scenarios, with a 5% likelihood of exceeding M 4.0.

Plain Language Summary Earthquakes have been triggered by natural gas extraction at the Groningen reservoir in the Netherlands since 1991 with the largest, a M 3.6, occurring in 2012. These earthquakes pose a risk to local communities and raise questions about future management of a resource that is strategically important to the country. In this study, we describe a computer model for the earthquakes at Groningen and the projections this model makes for future seismicity. We adapt new techniques to train our model on data and to quantify where uncertainty arises. Then, embracing the inherent unpredictability of earthquakes, we calculate the future earthquake rate for three different scenarios of gas extraction. Our model suggests that the largest earthquake in the period beginning February 2017 to the end of 2024 will be in the range M 3.0 to 4.0, with a 5% likelihood to exceed 4.0. However, it is not possible to predict when or where any particular event will occur.