Distinguishing high surf from volcanic long-period earthquakes

作者：Lyons John J^*; Haney Matthew M; Fee David; Paskievitch John F

来源：Geophysical Research Letters, 2014, 41(4): 1171-1178.

DOI：10.1002/2013GL058954

• Long-period seismicity
• volcanoes
• infrasound
• surf

Repeating long-period (LP) earthquakes are observed at active volcanoes worldwide and are typically attributed to unsteady pressure fluctuations associated with fluid migration through the volcanic plumbing system. Nonvolcanic sources of LP signals include ice movement and glacial outburst floods, and the waveform characteristics and frequency content of these events often make them difficult to distinguish from volcanic LP events. We analyze seismic and infrasound data from an LP swarm recorded at Pagan volcano on 12-14 October 2013 and compare the results to ocean wave data from a nearby buoy. We demonstrate that although the events show strong similarity to volcanic LP signals, the events are not volcanic but due to intense surf generated by a passing typhoon. Seismo-acoustic methods allow for rapid distinction of volcanic LP signals from those generated by large surf and other sources, a critical task for volcano monitoring. %26lt;br%26gt;Key Points %26lt;br%26gt;%26lt;list list-type=%26quot;bulleted%26quot; id=%26quot;grl51401-list-0001%26quot;%26gt; %26lt;list-item id=%26quot;grl51401-li-0001%26quot;%26gt;A swarm of LP earthquakes at Pagan volcano is associated with heavy surf %26lt;list-item id=%26quot;grl51401-li-0002%26quot;%26gt;Seismo-acoustic analyses distinguish volcanic and surf LP signals %26lt;list-item id=%26quot;grl51401-li-0003%26quot;%26gt;LP swarms from surf have a distinct periodicity not seen in volcanic LPs

• 出版日期2014-2-28