
A detailed analysis of some local earthquakes at Somma-Vesuvius
Author(s) -
Paolo Capuano,
U. Coppa,
Giuseppe De Natale,
F. di Sena,
C. Godano,
Claudia Troise
Publication year - 1999
Publication title -
annals of geophysics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.394
H-Index - 60
eISSN - 2037-416X
pISSN - 1593-5213
DOI - 10.4401/ag-3730
Subject(s) - seismology , geology , induced seismicity , earthquake swarm , peak ground acceleration , magnitude (astronomy) , acceleration , spectral analysis , ground motion , physics , classical mechanics , astronomy , quantum mechanics , spectroscopy
In this paper, we analyze local earthquakes which occurred at Somma-Vesuvius during two episodes of intense seismic swarms, in 1989 and 1995 respectively. For the selected earthquakes we have computed accurate hypocentral locations, focal mechanisms and spectral parameters. We have also studied the ground acceleration produced by the largest events of the sequences (ML 3.0), at various digital stations installed in the area during the periods of higher seismic activity. The main result is that seismicity during the two swarm episodes presents similar features in both locations and focal mechanisms. Strong site dependent effects are evidenced in the seismic radiation and strong amplifications in the frequency band 10-15 Hz are evident at stations located on the younger Vesuvius structure, with respect to one located on the ancient Somma structure. Furthermore, seismic stations show peak accelerations for the same events of more than one order of magnitude apart