S54B-02
Detecting and Cataloging Global Explosive Volcanism Using the IMS Infrasound Network
Friday, 18 December 2015: 16:15
307 (Moscone South)
Robin S Matoza, University of California, Santa Barbara, Department of Earth Science and Earth Research Institute, Santa Barbara, CA, United States, David N Green, AWE Blacknest, Reading, United Kingdom, Alexis LE Pichon, CEA Commissariat à l'Energie Atomique DAM, Arpajon Cedex, France, David Fee, University of Alaska Fairbanks, Geophysical Institute, Fairbanks, AK, United States, Peter M Shearer, University of California San Diego, La Jolla, CA, United States, Pierrick Mialle, CTBTO Preparatory Commission for the Comprehensive Nuclear Test-Ban Organization, Vienna, Austria and Lars Ceranna, BGR Federal Institute for Geosciences and Natural Resources, Hannover, Germany
Abstract:
Explosive volcanic eruptions are among the most powerful sources of infrasound observed on earth, with recordings routinely made at ranges of hundreds to thousands of kilometers. These eruptions can also inject large volumes of ash into heavily travelled aviation corridors, thus posing a significant societal and economic hazard. Detecting and counting the global occurrence of explosive volcanism helps with progress toward several goals in earth sciences and has direct applications in volcanic hazard mitigation. This project aims to build a quantitative catalog of global explosive volcanic activity using the International Monitoring System (IMS) infrasound network. We are developing methodologies to search systematically through IMS infrasound array detection bulletins to identify signals of volcanic origin. We combine infrasound signal association and source location using a brute-force, grid-search, cross-bearings approach. The algorithm corrects for a background prior rate of coherent infrasound signals in a global grid. When volcanic signals are identified, we extract metrics such as location, origin time, acoustic intensity, signal duration, and frequency content, compiling the results into a catalog. We are testing and validating our method on several well-known case studies, including the 2009 eruption of Sarychev Peak, Kuriles, the 2010 eruption of Eyjafjallajökull, Iceland, and the 2015 eruption of Calbuco, Chile. This work represents a step toward the goal of integrating IMS data products into global volcanic eruption early warning and notification systems. Additionally, a better characterization of volcanic signal detection helps improve understanding of operational event detection, discrimination, and association capabilities of the IMS network.
