Abstract
Recent developments in volcanic seismology include new techniques
to improve earthquake locations that have changed clouds of earthquakes
to lines (faults) for high-frequency events and small volumes for
low-frequency (LF) events. Spatial mapping of the b-value shows regions
of normal b and high b anomalies at depths of 3-4 and 7-10 km. Increases
in b precede some eruptions. LF events and very-long-period (VLP)
events have been recorded at many volcanoes, and models are becoming
increasingly sophisticated. Deep long-period (LP) events are fairly
common, but may represent several processes. Acoustic sensors have
greatly improved the study of volcanic explosions. Volcanic tremor
is stronger for fissure eruptions, phreatic eruptions, and higher
gas contents. Path and site effects can be extreme at volcanoes.
Seismicity at volcanoes is triggered by large earthquakes, although
mechanisms are still uncertain. A number of volcanoes have significant
deformation with very little seismicity. Tomography has benefited
from improved techniques and better instrumental arrays.
Users
Please
log in to take part in the discussion (add own reviews or comments).