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Matzel, Eric M.

Publications and source records attributed to Matzel, Eric M..

The Source Physics Experiment (SPE) Science Plan (Version 2.4c)

The Source Physics Experiment (SPE) series is a long-term NNSA research and development effort designed to improve U.S. arms control and nuclear nonproliferation verification and monitoring capabilities. The findings from the SPE will advance the United States’ nuclear explosion monitoring capabilities, particularly with respect to detection, discrimination and determination of yields associated with small nuclear explosions that can be lost amid the noisy seismo-acoustic background from other sources. The data generated from the SPE, a series of well-designed and recorded chemical explosions, will contribute to the development and validation of first-principles explosive source generated seismo-acoustic modeling codes. These codes will then facilitate the update of semi-empirical methods, currently based on historic test site data, such that key explosion observables can be reproduced, thus improving confidence in nuclear test monitoring in new areas and/or under novel emplacement conditions. The overall SPE project is comprised of both the development of the new explosion simulation codes and the chemical explosion test series. The chemical explosion test series will generate the empirical data required to both develop and validate the new simulation codes.

58 GEOSCIENCES↗

Moment Tensor Source-Type Analysis for the Democratic People's Republic of Korea-Declared Nuclear Explosions (2006-2017) and 3 September 2017 Collapse Event

The Democratic People's Republic of Korea (DPRK) conducted its sixth announced nuclear test on 3 September 2017 03:30 UTC (mb 6.1). There was an aftershock 8.5 min later (mb 4.1). Such aftershocks were noteworthy and often associated with post–nuclear explosion collapses. We performed moment tensor (MT) and network sensitivity solution (NSS) analysis using regional long-period surface-wave and first-motion (FM) polarities. We also extended this analysis to the previous five DPRK nuclear tests. The NSS results, which include MT solution uncertainties, show large isotropic components for the events and are within the population of other U.S. nuclear and collapse events on the fundamental lune. The FM data improved the NNS source-type resolution. The agreement between MT seismic moments and independent coda-envelope amplitudes indicated no biases with the Earth model error or poorly constrained seismic moment for shallow seismic sources. The MT for the collapse is not a pure implosion and consistent with an equivalent tensional closing crack mechanism and two-sided vertical point force.

58 GEOSCIENCES↗