Production-seismicity relationship in the Groningen field, NL: a multi-scale statistical and hazard assessment

Induced seismicity associated with hydrocarbon extraction represents a critical geohazard, particularly in structurally complex and densely populated regions. The Groningen gas field in the Netherlands is among the best-documented examples of seismicity triggered by reservoir depletion, where long-term production has progressively altered the subsurface stress state and reactivated pre-existing faults. Although the production-seismicity link is well established, its spatial variability across fault-bounded domains and response timing remain incompletely understood. This study presents a multi-scale statistical evaluation of the production–seismicity relationship, ranging from field-wide analysis to well-centered analysis. The well-centered analysis used 5 km and 10 km buffers around 16 production sites. Publicly available annual gas production records from the Netherlands Oil and Gas Portal (NLOG) were used for 1963–2023 at the field scale and 2003–2023 at the well scale. These data were combined with induced-earthquake records from the Royal Netherlands Meteorological Institute (KNMI) catalogue for 1991–2025. Pearson product-moment correlation was used to evaluate linear dependence, while Spearman’s rank correlation was used to assess monotonic relationships less sensitive to outliers. Time-lag correlations from 0 to 4 years were evaluated to test for delayed seismic response. Results showed that same-year correlations between production and event counts were generally weak at the field scale, whereas correlations increased when production preceded seismicity by approximately 3–4 years. Well-centered analysis indicated localized behavior, with correlations ranging from negligible to very strong. These results suggest that production-related seismicity in Groningen was influenced not only by production history, but also by cumulative depletion, delayed stress redistribution, and local fault architecture. By identifying where and how strongly seismicity correlates with production, this study clarifies the spatial and temporal variability of induced seismicity in Groningen and provides a statistical baseline for interpreting reservoir behavior, geological controls, and seismic hazard.