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High resolution 3D displacements maps of the L’ Aquila earthquake by applying SISTEM method to GPS and ENVISAT and ALOS DInSAR data.
(1) Istituto Nazionale di Geofisica e Vulcanologia, Piazza Roma, 2, 95123 Catania, Italy (2) Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata, 605, 00143 Roma, Italy
(3) Ecole Normale Superieure, , Paris, France (4) French Geological Survey, BRGM, , Orleans, France (5) National Observatory of Athens, , Athens, Greece
(6) Università di Catania, Viale Andrea Doria, 6, 95125 Catania, Italy
Guglielmino F. (1), Anzidei M.(2), Briole P.(3), De Michele M.(4), Panagiotis E.(5), Nunnari G.(6), Puglisi
G.(1) and Spata A.(6)
April 6, 2009, Mw 6.3 L’Aquila earthquake.
GPS DATA
CA-GeoNet was set up in 1999-2000 under ASI project (Anzidei et al., 2005)
GPS coseismic displacements of the April 6, 2009, Mw 6.3 L’Aquila earthquake.
On March 30, 2009, INGV installed five GPS receivers on selected benchmarks around the L’Aquila basin.
These were crucial, together with 3 CGPS stations, to resolve the near-field co-seismic deformation pattern properly, allowing direct observation of the details of co-seismic displacement
GPS observed and modeled coseismic displacements of the April 6, 2009, Mw 6.3 L’Aquila earthquake. Fault is 13x16 km.Observed (in black) and predicted (in blue) vectors.Red box: surface projection of the modeled source. Yellow star: epicenter of the mainshock (INGV, 2009).From Anzidei et al., 2009
Daily GPS time series for the near field GPS Stations during mainshock. Blue: CGPS stationsRed: CaGeoNet stations CA-GeoNet are crucial !Maximum displacements at CADO:Horizontal 10.39 ± 0.45 cm ; Vertical 15.64 ± 1.55 cm,NO significant deformations are recorded in the preseismic period
April 6, 2009, Mw 6.3 L’Aquila earthquake. Coseismic near field geodetic deformation
April 6, 2009, Mw 6.3 L’Aquila earthquake.
ALOS DATA
We analyzed ALOS PALSAR interferograms produced with images acquired along the 638 ascending tracks and relevant to the 3/7/2008 - 21/5/2009 time interval ( tbline = 322 days; Bperp = 665 m )
This is the co-seismic ground surface displacement seen by L-band (~23 cm) ALOS PALSAR data.
The PALSAR data, FBS mode (Fine Beam Single Polarisation) are kindly provided by JAXA (Japanese Space Agency) and ESA Earth watching Team.
One fringe corresponds to ~11.2 cm of surface displacement projected in the line of sight of the satellite (incidence ~34°).
April 6, 2009, Mw 6.3 L’Aquila earthquake.
ENVISAT DATA
Envisat-ascending Interferogram refers to 11/03/2009 - 15/04/2009(t bline = 35 days; Bperp = 227 m).
Envisat-descending Interferogram refers to 27/04/2008 – 12/04/2009(t bline = 350 days; Bperp = 44 m).
We are thankful to ESA, which made quickly available these images just after their acquisition in the framework of the Earth Watching project.
GPS and DInSAR INTEGRATION
GPSTime
Space
Low temporal resolutionHigh temporal resolution
Spatial distribution
Type 3D 1D (LOS)
DInSAR
Punctual measure
Goal: to take advantage of their complementary nature
SISTEMHigh Resolution 3D Surface Motion Map
GPS
ALOS ASCENDING
ENVISAT ASCENDING
ENVISAT DESCENDING
+
+
+
=
• SISTEM is based on elastic theory, and it provides the complete 3D strain and the rigid body rotation tensors.
• In order to derive high accuracy three-dimensional surface motion maps, we apply the novel SISTEM method [Guglielmino et al., submitted 2009]
• The SISTEM method performs an integration of GPS and DInSAR data for computing displacements on each point of the studied area.
(Simultaneous and Integrated Strain Tensor Estimation from geodetic and satellite deformation Measurements) SISTEM
• To achieve higher accuracy and constrain the 3D components of the displacements well, we improved the standard formulation of SISTEM approach, based on a single DInSAR data, in order to takeinto account both ascending and descending interferograms and DInSAR data acquired by ALOS and ENVISAT satellite.
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(Simultaneous and Integrated Strain Tensor Estimation from geodetic and satellite deformation Measurements) SISTEM
Remember that a DInSAR interferogram can be related to the components of the displacement vector of an arbitrary point P according to the following equation:
where [Sx,Sy,Sz] is a unit vector pointing from the point P toward the satellite. In order to integrate GPS and multiple DInSAR data, we propose the following matrix equations system :
For more details about the standard formulation of the SISTEM method, tomorrow presentation at the DInSAR session.
SISTEM RESULTSF. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
In the first line are reported the 3D displacement components. The result is compatible whit the surface evidence of the Paganica fault system, with a max lowering of 250 mm
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino In the second line the
associated standard error are reported. The horizontal error are lower than 15mm, and thank to the availability of ascending and descending data was possible to well constrain the vertical component (error<2.5 mm).
F. Di Paganica
F. Di Bazzano F.
F. Colle PraticcioloF. del Pettino
Di Mont.-Fossa
F. Roio-Canetra
F. Di Paganica
F. Di Bazzano F.
F. Colle PraticcioloF. del Pettino
Di Mont.-Fossa
F. Roio-Canetra
F. Di Paganica
F. Di Bazzano F.
F. Colle PraticcioloF. del Pettino
Di Mont.-Fossa
F. Roio-Canetra
In the last row are reported the principal 3D strain invariants.
SISTEM RESULTS3D components analysis
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
‐300
‐250
‐200
‐150
‐100
‐50
0
50
100
150
200
62 112 162 212 262
est
nord
up
PAGANICA FAULTMONTICCHIO‐FOSSA
FAULT
ROIO CANETRA FAULTMT. OCRE FAULT
The cross section show a complex kinematics whit a main displacements of of the Paganica fault, and involvement of several structure.
In order to individuate the main discontinuities on the ground motion field we performed a 3d component analysis
On the north-east area is evident an increase of the northward motion confirmed by the the GPS velocity field.
Surface faulting evidence
Evidence of coseismic faulting at Paganica. Trenches show also past ruptures.
April 6, 2009April 6, 2009Fault traceFault trace
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
SISTEM RESULTS3D strain analysis
‐100
‐50
0
50
100
150
200
250
300
350
400
450
62 112 162 212 262
Dilatation
Diff_rotation
Max Shear
PAGANICA FAULT
MONTICCHIO‐FOSSA FAULT
ROIO CANETRA FAULTMT. OCRE FAULT
The 3D strain analysis evidence a strong dilatation between the Paganica and Roio Canetra Fault associated whit a Max Shear Strain located along the Monticchio-Fossa fault. It is noteworthy a compression corresponding to the Paganica fault trace.
SISTEM RESULTSVolumetric dilatation
F. Di Paganica
F. Di Bazzano F. Di Mont.-Fossa
F. Roio-Canetra
F. Colle PraticcioloF. del Pettino
A detailed analysis of the Volumetric dilatation field reveal a compression along the surface trace of the Paganica and Monticchio fault, and in the area between this two faults.
Step-Over
Pop-Up
This kind of kinematics is compatible whit a step over fault geometry, a Pop-Up mechanism and diffuse surface fractures and damages.
L’Aquila earthquake: distribution of seismicity and faulting
• Shallow eq. (depths <10 km)• Seismicity distribution along the SE-NW
direction
From Chiaraluce et al., 2009
• Complex Extensional kinematic along the SW-NE direction
• Involvement of several structure• Agreement whit the history of the region
Important point:
The InSAR data, ranging over a time window longer than coseismic GPS dataset and include the contribution of other earthquakes of the sequence and therefore the post seismic deformation.
The deformation detected by SISTEM method are cumulative and are in good agreement with the seismological geodetic and geological data
SISTEM RESULTSConclusion
These results, which provide both accurate and fine spatial characterization of ground deformation, are hence promising for future studies aimed at improving the knowledge of the kinematic of the Paganica fault and identification of additional faults responsible of the seismic sequence and that have contributed to the observed ground deformation.
• GPS and DInSAR data are simultaneous integrated using the novel SISTEM method.
• Deformation field and relevant standard errors • Strain tensor and Rigid body rotation tensor
In particular the products are:
•The SISTEM method provide useful detailed and complete information of the ground deformation field.
SISTEM method at the FRINGE 2009TOMORROW
Thank you for your attention
