Services on Demand
Journal
Article
Indicators
Cited by SciELO
Access statistics
Related links
Cited by Google
Similars in SciELO
Similars in Google
Share
Earth Sciences Research Journal
Print version ISSN 1794-6190
Abstract
SANCHEZ, JOHN J et al. SPATIAL MAPPING OF THE B-VALUE AT GALERAS VOLCANO, COLOMBIA, USING EARTHQUAKES RECORDED FROM 1995 TO 2002 . Earth Sci. Res. J. [online]. 2005, vol.9, n.1, pp.29-35. ISSN 1794-6190.
The catalog of volcano-tectonic earthquakes at Galeras volcano, Colombia , was analyzed to determine the magnitude of completeness of the seismograph network and to explore the subsurface structure by mapping the b-value of the frequency-magnitude distribution. By using 8,435 well-located earthquakes between 1989-2002 we found the catalog to be complete above MD=0.26. The average b-value of 0.71 was found to be the result of an unintentionally stretched magnitude scale. The two- and three-dimensional mapping of b-value illuminates a vertically elongated structure beneath the active crater of Galeras down to a depth of 6 km, which may be associated with a conduit, or alternatively, with a shallow region of temporary magma storage. A structure with this geometry and location has not been found before in previous studies of b-value on volcanoes around the world.
Keywords : seismology; Galeras volcano; b-value; earthquarques.