Time-dependent seismic hazard and risk due to wastewater injection in Oklahoma

Abstract

In the past decade, Oklahoma has experienced unprecedented seismicity rates, following an increase in the volumes of wastewater that are being disposed underground. In this article, we perform a probabilistic assessment of the time-dependent seismic hazard in Oklahoma and incorporate these results into an integrated seismic risk model to assess the evolution of the statewide economic losses, including a conservative forecast through 2030. Our risk model employs an injection-driven earthquake rate model, a region-specific ground motion model, a recent Vs30 map, HAZUS exposure data and updated vulnerability curves for both structural and nonstructural elements, and contents. The calculations are performed using a stochastic Monte Carlo–based approach implemented in the OpenQuake engine. The resulting seismic hazard maps illustrate the incompatibility of the regional seismic provisions with the current seismicity. In 2015, in particular, the induced seismic hazard in several places in Oklahoma was higher than along the San Andreas fault. During the peak of seismicity in 2015, the seismic risk was 275 times higher than the background level, with the vast majority of losses originating from damages to nonstructural elements and contents. Our direct economic loss estimates are in reasonable agreement with the paid insurance claims, but show significant sensitivity to the ground motion model selection. The proposed risk model, with possible regular updates on the seismicity rate forecast, can help stakeholders define acceptable production levels.

A Strategy for Choosing Red‐Light Thresholds to Manage Hydraulic Fracturing Induced Seismicity in North America

“…HF induced earthquakes have been recognized around the globe: in the UK (Clarke et al., 2014), British Columbia (Babaie Mahani et al., 2017), Alberta (Schultz, Stern, et al., 2015, Schultz, Mei, et al., 2015), Ohio (Skoumal et al., 2015), Oklahoma (Skoumal et al., 2018), Arkansas (Yoon et al., 2017), Texas (Fasola et al., 2019), and China (Lei et al., 2019). While these earthquakes are only rarely induced by wells in susceptible locations (Atkinson et al., 2016; Galloway et al., 2018; Pawley et al., 2018), perceptions around their risks have caused public concern and impeded industry development (Ghofrani et al., 2019; Grigoratos et al., 2021). Specifically, public concerns about induced earthquakes tend to fixate on questions about their causes and their impacts on personal safety (Hillman et al., 2019).…”