The 1994-2004 Al Hoceima (Morocco) earthquake sequence ... - ESA

The 1994-2004 1994 2004 Al Hoceima (Morocco) earthquake sequence:
Conjugate fault ruptures deduced from InSAR
A. Akoglu (1), Z. Cakir* Cakir (2), M. Meghraoui (2), N. Jabour (3),
S. Belabbes (2), L. Ait-Brahim Ait Brahim (4), S. Ergintav (5)
(1) ITU, Istanbul, Turkey; (2) IPG Strasbourg, France; (3) CNRST, CNRST,
Rabat, Morocco; (4) U. Mohammed V, Rabat, Morocco Morocco
(5) TUBITAK MRC, Izmit, Turkey;
* presenter
ESA CAT-1 CAT 1 2532 project
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The 1994 and 2004 Al Hoceima earthquakes
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Proposed ruptures for the 1994 and 2004
earthquakes
1994
2004
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InSAR data
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InSAR data
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230
Solutions from InSAR
280
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1994
2004
Coseismic interferograms
ascending descending
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1994
2004
Location of the 1994 earthquake rupture
ascending descending
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1994
2004
Locations of the 1994-2004 1994 2004 earthquakes ruptures
ascending descending
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1994
2004
Modeling coseismic interferograms
with Poly3D
ascending descending
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Modeling the 2004 earthquake
Cakir et al., BSSA in press
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1994
2004
Best models for the 1994 & 2004
interferograms
ascending descending
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1994
2004
Residuals (observed – modeled)
ascending descending
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Modeled slip distributions
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Proposed fault ruptures for
the 1994 and 2004 earthquakes
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Proposed fault ruptures for
the 1994 and 2004 earthquakes
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Stress field in the Al Hoceima region
(See poster of Belabbes et al. for details)
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Summary of conclusions
• The 1994 & 2004 earthquakes in the Rif mountains took
place on N31°E and N43°W trending conjugate faults.
• Modeled faults are consistent with focal mechanism
solutions.
• The Rif is now deforming under a strike-slip regime.
• InSAR appears to be the best method for characterizing
the seismic source parameters, especially in the
absence of surface faulting.
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Acknowledgments ☺
European Space Agency provided Envisat ASAR
and ERS1-2 ERS1 2 SAR data under the projects:
AOTR.2436 (Interseismic Strain Accumulation and Earthquake Mechanisms Mechanisms
in
Turkey and Surrounding Regions Using Envisat and ERS SAR
Interferometry [PI:Z.Cakir [ PI:Z.Cakir]) ])
CAT1-2532 CAT1 2532 (Studying crustal deformation in Middle East and North Africa Africa
using
SAR Interferometry [PI:M.Meghraoui
[ PI:M.Meghraoui]) ])
Financial support is from EC project RELIEF and
APAME
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