0379890 - GFÚ 2013 RIV GB eng J - Journal Article
Pesicek, J. D. - Šílený, Jan - Prejean, S. G. - Thurber, C. H.
Determination and uncertainty of moment tensors for microearthquakes at Okmok Volcano, Alaska.
Geophysical Journal International. Roč. 190, č. 3 (2012), s. 1689-1709. ISSN 0956-540X. E-ISSN 1365-246X
R&D Projects: GA ČR GAP210/12/2235
Institutional research plan: CEZ:AV0Z30120515
Keywords : earthquake source observations * volcano seismology * body waves
Subject RIV: DC - Siesmology, Volcanology, Earth Structure
Impact factor: 2.853, year: 2012

Efforts to determine general moment tensors (MTs) for microearthquakes in volcanic areas are often hampered by small seismic networks, which can lead to poorly constrained hypocentres and inadequate modelling of seismic velocity heterogeneity. In addition, noisy seismic signals can make it difficult to identify phase arrivals correctly for small magnitude events. However, small volcanic earthquakes can have source mechanisms that deviate from brittle double-couple shear failure due to magmatic and/or hydrothermal processes. Thus, determining reliable MTs in such conditions is a challenging but potentially rewarding pursuit. We pursued such a goal at Okmok Volcano, Alaska, which erupted recently in 1997 and in 2008. The Alaska Volcano Observatory operates a seismic network of 12 stations at Okmok and routinely catalogues recorded seismicity.
Permanent Link: http://hdl.handle.net/11104/0210747