Cone Detectors That Operate at IMS Arrays Screen Background Seismicity at the DPRK Test Site

Date: 4/26/2019

Time: 08:45 AM

Room: Elliott Bay

We derive a template-based, nonlinear convex cone-type waveform detector that demonstrably reduces nuisance alarms on background seismicity. Our detector is more discriminating than a correlation detector, and screens out signals that partially correlate with the detector's waveform template. We quantify this discrimination power with physical parameters that depend on source and background seismicity, that include the relative magnitude between ``template'' and ``target'' sources. We then use seismic records of several events that locate at or near the North Korean test site from an IMS array (USRK) to quantify the capability of this detector to screen non-target explosion-sources that spatially separate from the template source. By applying source-receiver reciprocity, we thereby calculate values for screening capability improvement versus template-target explosion source separation. Our results show a demonstrable improvement in both the observed and predictive capability, over that of the correlation detector, for explosion-triggered target signals contaminated by background seismicity.

Presenting Author: Joshua D. Carmichael

Authors