Regional Small-Event Identification Using Networks and Arrays of Seismic and Acoustic Sensors

摘要

Our work under this contract has had three primary objectives, but with the common theme of using seismic data to distinguish mining blasts from all other event types. We have used spectral characteristics of whole waveforms to discriminate industrial blasts from instantaneous explosions and earthquakes. We applied the automated time-frequency discriminant (AFTD) to several datasets to test transportability and robustness of the algorithm. The main conclusions of this work, described in the first section of this report, are that the method can be applied without significant modifications to broadly distributed datasets, but the method has limited range due to attenuation. In the second section, we describe our use of seismic waveforms between .05 and 10 Hz to characterize well ground-truthed mine blasts in Wyoming. Included in this section is preliminary modeling of events in this region. The report's third section summarizes the main findings of a review article written by Brian Stump, the PI, Craig Pearson and Vindell Hsu and published in the Reviews of Geophysics 4O(4), 1011, doi:l0.1029/ 1998 RGOOOO48, 2002. In this article, we assess the state-of-the-art in global monitoring of mining blast activity and explore avenues for further research needed in this area.