Improved In-Water Explosion Detection by Hydrophone Triads and T-phase Stations

Abstract:

We compare the standard detection scheme employed for hydroacoustic data with an array power detector. The new detection approach offers marginal improvement in signal-to-noise ratio due to the small number of elements, but improves performance for small signals that sit at the threshold of single-station detection. We test the new scheme with a ground-truth dataset from a marine seismic experiment off the coast of Japan and find three times more detections of the small explosions used in the experiment for a hydroacoustic array off Juan Fernandez Island at a distance of nearly 16300 km. We also report detections at several T-phase stations in the Pacific, including Socorro Island at a distance of nearly 10500 km. We plan to analyze features of these detections with the aim of improving in-water explosion detection at T-phase stations.

Prepared by LLNL under Contract DE-AC52-07NA27344.