Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/10776
Authors: | Villani, Fabio* Improta, Luigi* Pucci, Stefano* Civico, Riccardo* Bruno, P. P. G.* Pantosti, Daniela* |
Title: | Investigating the architecture of the Paganica Fault (2009Mw6.1 earthquake, central Italy) by integrating high-resolution multiscale refraction tomography and detailed geological mapping | Journal: | Geophysical Journal International | Series/Report no.: | /208 (2017) | Issue Date: | 2-Nov-2017 | DOI: | 10.1093/gji/ggw407 | Abstract: | We present a 2-D subsurface image of the Paganica Fault from a high-resolution refraction tomography and detailed geological investigation carried out across part of the northwestern segment of the 20-km-long Paganica–San Demetrio fault-system, and which was responsible of the 2009 April 6 Mw 6.1 L’Aquila earthquake (central Italy). We acquired two seismic profiles crossing the Paganica basin with a dense-wide aperture configuration. More than 30 000 P wave first-arrival traveltimes were input to a non-linear tomographic inversion. The obtained 250–300 m deep 2-D Vp images illuminate the shallow portion of the Paganica Fault, and depict additional unreported splays defining a complex half-graben structure. We interpret local thickening of low-Vp (<2400 m s−1) and intermediate-Vp (2600–3400 m s−1) regions as syn-tectonic clasticwedges above a high-Vp (3800–5000ms−1) carbonate basement. These results are condensed in a 4.2-km-long section across the Paganica basin, clearly indicating that the Paganica Fault is a mature normal fault cutting the whole upper ∼10 km of the crust. We evaluate a minimum cumulative net displacement of 650 ± 90 m and a total heave of 530 ± 65 m accomplished by the Paganica Fault, respectively. In the conservative hypothesis that the extension started during the Gelasian (1.80–2.59 Ma),we obtain a minimum long-term slip-rate of 0.30 ± 0.07 mm yr−1 and an extension-rate of 0.25 ± 0.06 mm yr−1, respectively. Considering the regional averaged extensional field of ∼1 mm yr−1 obtained from geodetic and geological analyses at 104 yr timescale, we infer that the Paganica Fault accounts for ∼20 per cent of the NE-extension affecting this zone of the central Apennines axis due to the concurrent activity of other parallel normal fault-systems nearby (e.g. the Liri, Velino-Magnola, L’Aquila-Celano and Gran Sasso fault-systems). | Description: | This article has been accepted for publication in Geophysical Journal Internationa ©: 2017 Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. |
Appears in Collections: | Article published / in press |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
Paganica_VillaniGJI2016_pubblished-lowres.pdf | pdf manuscript | 2.23 MB | Adobe PDF | View/Open |
WEB OF SCIENCETM
Citations
50
7
checked on Feb 10, 2021
Page view(s)
419
checked on Apr 17, 2024
Download(s)
153
checked on Apr 17, 2024