Probabilistic source location of explosion quakes at Stromboli volcano estimated with double array data

Data from two dense arrays of short-period seismometers are used to retrieve source locations of the explosion quakes at Stromboli volcano. Slowness vectors estimated at both arrays with the zero-lag cross-correlation technique constitute the experimental data set. A probabilistic approach based on a grid search spanning the volcano interior is used to calculate the probability of the source location. Results depict a shallow source, located beneath the crater area, at depths not greater than 500 m below the surface. Results are slightly different from, but comparable to, those obtained in a companion experiment carried out in the same time period using a broad-band seismometer network, which show a source shifted some hundreds of meters northwest of the crater area. The method is revealed to be effective and useful for future studies having the purpose of real-time tracking of the explosion quakes and tremor. (C) 2003 Elsevier B.V. All rights reserved.