Robust location of surface explosions by a network of acoustic arrays

This study experimentally assesses a capability of a network, comprised of several small tripartite infrasound arrays, to locate accurately surface explosion sources at distances of several tens of kilometres. The location procedure, we developed, utilises first arrival phase delays and includes two main stages. Firstly a preliminary source location is obtained as intersection point of back-azimuths estimated for each individual array. Then using jointly time delays from different arrays, a refined location is found via non-linear grid-search optimization technique. The procedure features are: independency from a source-station travel time model, reduced influence of the outliers, optional adaptation to the varying multi-channel noise. High location accuracy (a few hundred meters) was achieved for field experimental on-surface explosions in Sayarim valley, Israel, recorded by special tripartite infrasound arrays.