SISMA: Workshop finaleASI, 4 maggio 2011 Il Progetto Progetto SISMA: razionale, attività e...
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Transcript of SISMA: Workshop finaleASI, 4 maggio 2011 Il Progetto Progetto SISMA: razionale, attività e...
SISMA: Workshop finale ASI, 4 maggio 2011
Il Progetto Progetto SISMA:
razionale, attività e principali risultati
Roberto Sabadini
Università degli Studi di Milano
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA new approach towards the understanding of SISMA new approach towards the understanding of earthquake generation and seismic hazard mitigation builds earthquake generation and seismic hazard mitigation builds
over three major concepts:over three major concepts:
taking advantage of the new generation of DINSAR and GPS deformation data at the Earth’s surface in conjunction with seismic flow monitoring
which in turn allows us
building an integrated geophysical, geodetic and seismological scheme to disclose stress build up within the gouge of sesmic active faults for a deterministic approach of earthquake cycle description
which in turn allows us
overcoming the obvious shortcomings of the old approach to seismic hazard mitigation based on a purely probabilistic approach
SISMA: Workshop finale ASI, 4 maggio 2011
Restrained areasFor SAR and GPS
Establishment of a localnetwork of GPS Receiver
set uo on monumented sites,co-located with proper CAT
GeophysicalForward Modellingof stress build up in the fault gouge
PermanentGPS
Formalized analysisof seismicity update
Evaluation of seismic hazard
GPS data processing to retrieve
continuously updated deformation and
velocity maps
Acquisition of the historicalSAR images of the area andrequest to running Missions
(e.g. Cosmo Skymed) to planning new observations.
SAR data processing to retrieve
continuously updated deformation and
velocity maps
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
stima deformazione: TIN vs Poligoni (da ZS9)
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
SISMA: Workshop finale ASI, 4 maggio 2011
Northern Region, M o=5.4
6 .5 5 .4 5 .8 6 .0
1965 1975 1985 1995 2005
5 .5 5 .6 5 .5
Central Region, M o=5.65 .86 .0 6 .5
5 .76 .0
1955 1965 1975 1985 1995 2005
5 .7
Southern Region, M o=5.65 .86 .0 6 .55 .8
1955 1965 1975 1985 1995 2005
5 .76.5 5 .4 5 .8 6 .0
1965 1975 1985 1995 2005 2015
5.55 .65 .5
5 .86 .0 6.5
5 .76 .0
1955 1965 1975 1985 1995 2005 2015
5 .7 6.35 .86 .0 6 .55 .8
1955 1965 1975 1985 1995 2005 2015
5.7
M5.5+M5.5+ M6.0+M6.0+ M6.5+M6.5+
CNCNalgorithmalgorithmTimes of Increased Probability for the occurrence of events with M>Mo within the monitored regions
Monitored region
Alerted region
M8S M8S algorithmalgorithm
SISMA: Workshop finale ASI, 4 maggio 2011
Geodetic and seismic integration: IBAY map
Red = geodetic anomalies plus seismic alertGreen = neither geodetic anomalies
nor seismic alertYellow = geodetic anomaliesOrange = seismic alert
The numbers in the red zones give the relative alert value.
SISMA: Workshop finale ASI, 4 maggio 2011
Local ground shaking Local ground shaking scenario for the Gubbio scenario for the Gubbio
sitesite
Ground motion Ground motion scenarios scenarios
at local scaleat local scale
Detailed scenarioDetailed scenarioss of of ground motionground motion, , including including site effectssite effects ((2D sections 2D sections
describing the mechanical describing the mechanical properties properties
of the sites)of the sites), are defined , are defined at the local scale at the local scale
for for the the alerted faults.alerted faults.
Synthetic seismograms
Spectral amplifications
2D laterally heterogeneous
local profile
SISMA: Workshop finale ASI, 4 maggio 2011
Conclusions Although the seismic classification of the Italian territory has been
recently revised, the evaluation of seismic hazard continue to be based on the traditional probabilistic approach, i.e. on the probabilistic analysis of earthquake catalogue and of ground motion information, retrieved by macroseismic observations and instrumental recordings, that may lead to severe underestimations of seismic hazard.
Recently this approach showed its limitation in providing a reliable seismic hazard assessment, possibly due to the insufficient information about historical seismicity, which can introduce relevant errors in the purely statistical approach mainly based on the seismic history.