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Distal volcano-tectonic seismicity near Augustine Volcano

Professional Paper 1769-6

Chapter 6 of Power, J.A., Coombs, M.L., and Freymueller, J.T., eds., The 2006 eruption of Augustine Volcano, Alaska
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Abstract

Clustered earthquakes located 25 km northeast of Augustine Volcano occurred more frequently beginning about 8 months before the volcano?s explosive eruption in 2006. This increase in distal seismicity was contemporaneous with an increase in seismicity directly below the volcano's vent. Furthermore, the distal seismicity intensified penecontemporaneously with signals in geodetic data that appear to reveal a transition from magmatic inflation of the volcano to dike injection. Focal mechanisms for five events within the distal cluster show strike-slip-fault movement. Directly above the earthquake cluster, shallow (<5 km deep) folds and faults mapped using multichannel seismic-reflection data strike northeast, parallel to the regional structural grain. About 10 km northeast of Augustine Volcano, however, the Augustine-Seldovia arch, an important trans-basin feature, strikes west and intersects the northeast-striking structural zone. We propose that the fault causing the distal earthquake cluster strikes northwest, subparallel to the arch, and is a right-lateral strike-slip fault. Future earthquake monitoring might show whether increasing activity in the remote cluster can aid in making eruption forecasts.

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Distal volcano-tectonic seismicity near Augustine Volcano
Series title:
Professional Paper
Series number:
1769
Chapter:
6
Edition:
-
Year Published:
2010
Language:
English
Publisher:
U.S. Geological Survey
Description:
p. 119-128
Online Only (Y/N):
Y
Additional Online Files(Y/N):
N