阿拉斯加火山的噴發和動盪前的顯著b值時間變化的系統性研究

Changes in seismicity parameters is often utilized for the purpose of forecasting eruptive activity at volcanoes worldwide. One of these parameters is the slope of the Gutenberg-Richter law, known as the b-value, whose temporal variation is studied here as an indicator of volcanic activity. This proposal aims at a systematic investigation for significant changes in the temporal evolution of bvalues at active volcanoes in Alaska. At least five of these volcanoes (Great Sitkin, Makushin, Martin, Redoubt, and Spurr) could be selected in order to reconstruct the b-value variation over a multiyear period that covers unrest episodes and eruptions. The Alaska Volcano Observatory catalog will be used,which covers seismicity from October 1989 until present and contains the locations of more than 120,000 volcano-tectonic earthquakes along with their local or duration magnitudes. Results will be utilized in order to improve volcano alert schemes at stratovolcanoes as well as for the purpose of comparing observed data with models of the mechanical properties of volcanic rocks derived from laboratory experiments.