Earthquake hazard and risk analysis for natural and induced seismicity: towards objective assessments in the face of uncertainty

Abstract

The fundamental objective of earthquake engineering is to protect lives and livelihoods through the reduction of seismic risk. Directly or indirectly, this generally requires quantification of the risk, for which quantification of the seismic hazard is required as a basic input. Over the last several decades, the practice of seismic hazard analysis has evolved enormously, firstly with the introduction of a rational framework for handling the apparent randomness in earthquake processes, which also enabled risk assessments to consider both the severity and likelihood of earthquake effects. The next major evolutionary step was the identification of epistemic uncertainties related to incomplete knowledge, and the formulation of frameworks for both their quantification and their incorporation into hazard assessments. Despite these advances in the practice of seismic hazard analysis, it is not uncommon for the acceptance of seismic hazard estimates to be hindered by invalid comparisons, resistance to new information that challenges prevailing views, and attachment to previous estimates of the hazard. The challenge of achieving impartial acceptance of seismic hazard and risk estimates becomes even more acute in the case of earthquakes attributed to human activities. A more rational evaluation of seismic hazard and risk due to induced earthquakes may be facilitated by adopting, with appropriate adaptations, the advances in risk quantification and risk mitigation developed for natural seismicity. While such practices may provide an impartial starting point for decision making regarding risk mitigation measures, the most promising avenue to achieve broad societal acceptance of the risks associated with induced earthquakes is through effective regulation, which needs to be transparent, independent, and informed by risk considerations based on both sound seismological science and reliable earthquake engineering.

Ground-motion prediction models for induced earthquakes in the Groningen gas field, the Netherlands

“…Some readers may question the relevance of this work in light of the political decision by the Dutch government to close the Groningen gas field (e.g. Bommer 2022). There are several reasons, however, why seismic hazard and risk assessments, and hence the ground-motion models, for the field, remain relevant.…”

“…Several early versions of the GMPM included predictions for PGV, as well as response spectra accelerations and durations, for potential applications to risk analysis of some infrastructure lifelines, but this was discontinued since we were not aware of any such applications in practice. However, the need arose for a PGV model to be used in the evaluation of damage claims, the cumulative value of which has reached unprecedented levels (Crowley et al 2019;Bommer 2022). Since this model was to be applied only within the magnitude range of the data, an empirical groundmotion prediction equation (GMPE) was considered sufficient.…”

Seismic roulette: Hazards and risks

“…In most recent publications, the supporters of widespread PSHA limit their discussion of deterministic approaches-DSHA and NDSHA-to a note on "the diehard determinists" who "have generally tried to utterly discredit PSHA" (Baker, Bradley, & Stafford, 2021;Bommer, 2022), forgetting that, in fact, it's the PSHA application results since 1999 (and earlier) with many publications, have failed evidently. Jordan, Marzocchi, Michael, and Gerstenberger (2014) have referenced (Peresan et al, 2012), which reference fully reveals the qualities, attributes and applicability of NDSHA to "Operational earthquake forecast/prediction" with direct attention called in the Abstract to the "very unsatisfactory global performance of Probabilistic Seismic Hazard Assessment at the occurrence of most of the recent destructive earthquakes."…”

“…In most recent publications, the supporters of widespread PSHA limit their discussion of deterministic approaches—DSHA and NDSHA—to a note on “the diehard determinists” who “have generally tried to utterly discredit PSHA” (Baker, Bradley, & Stafford, 2021; Bommer, 2022), forgetting that, in fact, it's the PSHA application results since 1999 (and earlier) with many publications, have failed evidently.…”

Methods for assessing the epistemic uncertainty captured in ground-motion models

“…incomplete earthquake catalogues, a lack of local strong-motion data and sparse measurements of geotechnical and geophysical characteristics) from the region surrounding the site and from the site itself. The reader is referred to the recent landmark article on this topic by Bommer (2022).…”