Please use this identifier to cite or link to this item:
Authors: Napoli, R.* 
Currenti, G.* 
Del Negro, C.* 
Di Stefano, A.* 
Greco, F.* 
Boschi, E.* 
Title: Magnetic features of the magmatic intrusion that occurred in the 2007 eruption at Stromboli Island (Italy)
Issue Date: 2011
Series/Report no.: /73 (2011)
DOI: 10.1007/s00445-011-0473-0
Keywords: Stromboli Island
Magnetic monitoring
Piezomagnetic field
Stress field
Subject Classification04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring 
Abstract: Significant changes in the local magnetic field marked the resumption of eruptive activity at Stromboli volcano on February 27, 2007. After differential magnetic fields were obtained by filtering out external noise using adaptive filters and seasonal thermal noise using temperature data, we identified step-like changes of 1–4 nT coincident with the opening of eruptive fissures in the upper part of the Sciara del Fuoco. The magnetic variations detected at two stations are closely related to the propagation of a shallow NE–SW magmatic intrusion extending beyond the summit craters area. These observations are consistent with those calculated using piezomagnetic models in which stress-induced changes in rock magnetization are produced by the magmatic intrusion. No significant magnetic changes were observed when the first fractures opened along the NE crater rim. Indeed, the stressinduced magnetization caused by this magmatic activity is expected to be too low because of the structural weakness and/or thermal state of the summit area. The continuous long-term decay characterizing the post-eruptive magnetic pattern can be related to a time-dependent relaxation process. A Maxwell rheology was assumed and the temporal evolution of the piezomagnetic field was evaluated. This allowed us to estimate the rheological properties of the medium; in particular, an average viscosity ranging between 1016 and 1017 Pa⋅s was a relaxation time τ of about 38 days.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
Napoli et al 2011.pdf1.44 MBAdobe PDFView/Open
Show full item record

Page view(s)

Last Week
Last month
checked on Aug 17, 2018


checked on Aug 17, 2018

Google ScholarTM