%0 Journal Article %1 ferrucci_etal:1992 %A Ferrucci, F. %A Hirn, A. %A De Natale, G. %A Virieux, J. %A Mirabile, L. %D 1992 %J Journal of Geophysical Research %K geophysics seismology %N B11 %P 15351--15359 %R 10.1029/92JB00888 %T P-SV conversions at a shallow boundary beneath Campi Flegrei caldera (Italy): Evidence for the magma chamber %U http://dx.doi.org/10.1029/92JB00888 %V 97 %X Seismograms from an active seismic experiment carried out at Campi Flegrei caldera (near Naples, Italy) show a large-amplitude SV-polarized shear wave, following by less than 1.5-s P waves reflected at wide angle from a deep crustal interface. Early arriving SV-polarized waves, with the same delay to direct P waves, are also observed in seismograms from a regional, 280-km-deep, magnitude 5.1 earthquake. Such short delays of S to P waves are consistent with a P-SV conversion on transmission occurring at a shallow boundary beneath the receivers. The large amplitude of the converted-SV phase, along with that the P waves are near vertical, requires a boundary separating a very low rigidity layer from the upper caldera fill. The converted phases are interpreted as a seismic marker of a magma chamber. The top of this magma chamber is located slightly deeper than the deepest earthquakes observed during the 1982-1984 unrest of Campi Flegrei.

@article{ferrucci_etal:1992, abstract = {Seismograms from an active seismic experiment carried out at Campi Flegrei caldera (near Naples, Italy) show a large-amplitude SV-polarized shear wave, following by less than 1.5-s P waves reflected at wide angle from a deep crustal interface. Early arriving SV-polarized waves, with the same delay to direct P waves, are also observed in seismograms from a regional, 280-km-deep, magnitude 5.1 earthquake. Such short delays of S to P waves are consistent with a P-SV conversion on transmission occurring at a shallow boundary beneath the receivers. The large amplitude of the converted-SV phase, along with that the P waves are near vertical, requires a boundary separating a very low rigidity layer from the upper caldera fill. The converted phases are interpreted as a seismic marker of a magma chamber. The top of this magma chamber is located slightly deeper than the deepest earthquakes observed during the 1982-1984 unrest of Campi Flegrei.}, added-at = {2012-09-01T13:08:21.000+0200}, author = {Ferrucci, F. and Hirn, A. and De Natale, G. and Virieux, J. and Mirabile, L.}, biburl = {https://www.bibsonomy.org/bibtex/2331df273937ae86e9bc1eb5ec96fbf1f/nilsma}, doi = {10.1029/92JB00888}, interhash = {a216234519a50805e8c10d5283cea008}, intrahash = {331df273937ae86e9bc1eb5ec96fbf1f}, issn = {0148-0227}, journal = {Journal of Geophysical Research}, keywords = {geophysics seismology}, month = oct, number = {B11}, pages = {15351--15359}, timestamp = {2021-02-09T13:27:42.000+0100}, title = {P-SV conversions at a shallow boundary beneath Campi Flegrei caldera (Italy): Evidence for the magma chamber}, url = {http://dx.doi.org/10.1029/92JB00888}, volume = 97, year = 1992 }