Recursive detection of swarms of volcanic long-period seismicity in Marie Byrd, Antarctica

Abstract:

A poorly constrained rift system supports volcanism in Marie Byrd West Antarctica. The ice cover is thick, making it difficult to investigate the rift system and volcanos with standard geophysical and geological methods. Volcanic activity has been observed throughout 2010 and 2011 during the International Polar Year POLENET/ANET seismic deployment. The continuous seismic data from this network recorded two swarms of long period earthquakes in February 2010 and in April 2011. These swarms contain information about the mechanisms and magmatic fluid transport mechanics within the plumbing systems of the active volcanos. We perform a systematic detection of long-period seismicity, using seismic events as templates in a matched-filter search. We start with a single manually chosen templates with a high signal-to-noise. We develop a recursive matched filter approach to spatially explore the long-period earthquake source region, using newly detected events as templates. We relate the characteristics of the long-period seismicity and their swarms to the timing of the volcanic eruptions, and the physical processes beneath the volcanos.