Seismoacoustic Source Localization: Case Study from the Accurate Energetic Systems Explosion

Abstract

This study investigates seismoacoustic source localization using the 10 October 2025 Accurate Energetic Systems accidental explosion in Tennessee as a case study. Two complementary methods are tested: the Seismoacoustic Bayesian Event Locator (SABEL) algorithm, which combines picked seismic and infrasound arrival times with seismic velocity and infrasound celerity-prior models to estimate a posterior distribution of source location and origin time, and a seismoacoustic reverse time migration (RTM) approach that backpropagates enveloped waveforms. For SABEL, three infrasound celerity priors are evaluated, including a propagation-model-informed celerity–range prior. Joint seismoacoustic solutions reduce location uncertainty relative to seismic-only; for example, a simple tropospheric celerity prior reduces the 90% confidence region by ∼50% while maintaining kilometer-scale accuracy, and the celerity–range prior yields the smallest infrasound-only uncertainties and improves the joint solution. RTM provides a waveform-based mechanism for detection and association, but origin times are biased late when using infrasound alone; adding seismic data substantially improves timing (to a few seconds) and produces a narrower spatiotemporal stack despite a modest increase in spatial misfit relative to the best-single-phenomenology RTM result. Overall, the results highlight the value of seismoacoustic data fusion for improved localization and demonstrate how RTM-derived associations can support arrival-time-based methods in monitoring workflows.