Options
Richwalsky, S.
Loading...
2 results
Now showing 1 - 2 of 2
- PublicationOpen Accessask 6 - Gubbio - Deliverable D21: Geological model of the Gubbio basin (Italy) for the characterization of local seismic response(2007-07)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Fiorini, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Pacor, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Bindi, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Rovelli, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Cara, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Di Giulio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Milana, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Monachesi, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia ;Nieto, D.; INOGS Trieste ;Bohm, G.; INOGS Trieste ;Albarello, D.; univerita' Siena ;D'Amico, V.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Picozzi, M.; univerita' Siena ;Mucciarelli M.; universita' Basilicata ;Scarascia Mugnozza, G.; universita' La Sapienza Roma ;Rivellino, S.; universita' La Sapienza Roma ;Menichetti, M.; universita' Urbino ;Parolai, S.; GFZ Postdam ;Richwalsky, S.; GFZ Postdam ;Orpsal, I; GFZ Postdam; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; Within the framework of the project S3 “Ground shaking scenarios for some strategic areas in Italy-Task6” the town of Gubbio has been selected as a test site to compute ground motion taking into account finite fault and site effects. Gubbio is located in central Italy, on the northern slopes of one of the many valleys characterising the central Appennines. The historical settlement is located on a rocky slope, while new developments extend on the Quaternary fluvio-lacustrine deposits filling the basin. The Gubbio basin was chosen as a test site for a number of reasons: its geomorphological setting is very common in central and southern Italy, the area is characterised by frequent near events of moderate magnitude (Mmax 6) and large amplifications were observed there for the Colfiorito seismic sequence of the 1997/98. In order to understand the mechanisms controlling the 3D seismic response of the basin, a subsurface model has been constructed. The reconstruction of the model has been done using data coming from different surveys (figure A). Several active and passive seismic measurements have been carried out in the plain, also favoured by the intense seismic activity typical of the area. These investigations mainly consisted of monitoring activities of 4 temporary transects of seismometric stations, operating between June 2005 and May 2006 and described in detail in PS3- Deliverables D22-D23. Two transects have been positioned perpendicularly to the valley axes (GFZ and Ge2 Transects), one parallel (INGV transect) and one near Gubbio (Ge1 transect). More than 300 local and regional earthquakes have been recorded, with maximum magnitude equal to 4. A 2D array was run as well from June to September 2006, to better understand the generation of surface waves. All data are collected in a GIS (Progetto S3 Deliverable D23) Parallel to these activities, ambient noise data have been collected in the field for 90 sites, using the single station technique for the estimation of the fundamental resonance frequencies. Furthermore, 4 noise measurements with a seismic array have been collected to build an S-wave velocity profile of soft sediments, considered representative for the whole plain. The geometry of the basin below 500 m of depth has been investigated through the acquisition of an active seismic line 4.5 km long, in correspondence of one of the transects. This has been used to perform a tomography of arrival times which allowed to recognise the position and shape of the reflecting horizons. As a final step the first 30 metres of deposits have been characterised over a 30 km2 area, using both stratigraphic investigations provided by the Gubbio Municipality and data collected from in-situ surveys and lab tests. In this deliverable we describe the input data for the 3D model of the Gubbio basin and we outline the steps performed to define the geometry, the layers and their seismic properties on the base of the experimental data collected during the project and of the available geological information.295 583 - PublicationOpen AccessTask 6 - Gubbio - Deliverables D22-D23: Shaking scenarios including site effects(2007-07)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Bindi, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Fiorini, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Pacor, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Luzi, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Rovelli, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Cara, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Di Giulio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Milana, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Monachesi, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Albarello, D.; Universita' di Siena ;D'Amico, V.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Picozzi, M.; Universita' di Siena ;Mucciarelli, M.; Universita' Basilicata ;Ferretti, G.; universita' di Genova ;Emolo, A.; Universita' Napoli ;Parolai, S.; GFZ Potsdam ;Richwalsky, S.; GFZ Potsdam; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; Within the Italian Project S3 (DPC-INGV) “Shaking seismic scenarios in area of strategic and/or priority interest” the urban area of Gubbio has been chosen as a test site for the calculation of ground shaking scenarios for forecasting purposes. The area has been selected because the urban and / or geomorphologic characteristics of the town of Gubbio and its surrounding are good representatives of many areas in Central Italy: an historical centre of high cultural and artistic value founded on a rocky hillside with new residential and industrial areas developed on the alluvial plain. A great deal of effort has been put in the seismic characterisation of the Gubbio basin, since the general purpose of this work has been the quantification of site effects in intra-mountain basins. Recent studies have shown in fact that significant site effects take place in the Eugubina plain, as evidenced by the generation of surface waves. In particular, the strong motions recorded at the accelerometric station GPB, belonging to the RAN (Rete accelerometrica italiana), installed within the alluvial basin, shows strong amplification and lengthening of significant duration respect to rock sites (Pacor et al; 2007). Several investigations with active and passive seismic survey techniques have been planned and carried out in the plain, also favoured by the intense seismic activity typical of the area (see PS3-Deliverable 21). All data are collected in a GIS herewith enclosed (section 7). The estimates of the empirical transfer functions in the basin have been related to the monitoring activities of 4 temporary transects of seismometric stations (Figure 1.1), operating between June 2005 and May 2006 and described in this Deliverable. The velocemetric records are collected in PS3-Deliverable D26 The amplitude transfer functions for sites corresponding to the stations installed in the basin have been determined by applying three different methods, namely the horizontal-to-vertical spectral ratio (H/V), the standard spectral ratio (SSR) and the generalized inversion technique (GIT).179 416