Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/7140
AuthorsMarzorati, S.* 
Ladina, C.* 
Falcucci, E.* 
Gori, S.* 
Saroli, M.* 
Ameri, G.* 
Galadini, F.* 
TitleSite effects “on the rock”: the case of Castelvecchio Subequo (L’Aquila, central Italy)
Issue Date2011
Series/Report no.3/9 (2011)
DOI10.1007/s10518-011-9263-5
URIhttp://hdl.handle.net/2122/7140
KeywordsSite effects
Rock site
Ambient seismic noise
Structural characteristics
Geomechanical analyses
Jointing
Castelvecchio Subequo
2009 L'Aquila earthquake
central Italy
Subject Classification04. Solid Earth::04.06. Seismology::04.06.04. Ground motion 
AbstractThe April 6, 2009 L’Aquila earthquake was responsible for an “anomalous”, relatively high degree of damage (i.e. Is 7 MCS scale) at Castelvecchio Subequo (CS). Indeed, the village is located at source-to-site distance of about 40 km, and it is surrounded by other inhabited centres to which considerably lower intensities, i.e. Is 5-6, have been attributed. Moreover, the damage was irregularly distributed within CS, being mainly concentrated in the uppermost portion of the old village. Geophysical investigations (ambient seismic noise and weak ground motions analyses) revealed that site effects occurred at CS. Amplifications of the ground motion, mainly striking NE-SW, have been detected at the uppermost portion of the carbonate ridge on which the village is built. Geological/structural and geomechanical field surveys defined that the CS ridge is affected by sets of fractures, joints and shear planes – mainly roughly NW-SE and N-S trending – that are related to the deformation zone of the Subequana valley fault system and to transfer faults linking northward the mentioned tectonic feature with the Middle Aterno Valley fault system. In particular, our investigations highlight that seismic amplifications occur where joints set NW-SE trending are open. On the other hand, no amplification is seen in portions of the ridge where the bedrock is densely fractured but no open joints occur. The fracture opening seems related to the toppling tendency of the bedrock slabs, owing to the local geomorphic setting. These investigations suggest that the detected amplification of the ground motion is probably related to the polarization of the seismic waves along the Castelvecchio Subequo ridge, with the consequent oscillation of the rock slabs perpendicularly to the fractures azimuth.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
Marzorati_et_al.pdfMain article1.49 MBAdobe PDFView/Open
Show full item record

Page view(s)

89
checked on May 27, 2017

Download(s)

312
checked on May 27, 2017

Google ScholarTM

Check

Altmetric