| Popis: |
Northern Algeria experienced moderate and large earthquakes (with Mw > 6) during the last decades due to the convergence between the African and Eurasian plates. We conduct the joint analysis of multi-temporal SAR-dataset (1995 to 2021), combined with the GPS velocities (2007 to 2018) and seismotectonic studies in the Chlef-El Asnam and Zemmouri Mitidja regions of the Tell Atlas. The multidisciplinary approach adopted in this study has the advantage of integrating the interseismic (paleoseismology, tectonic geomorphology), the coseismic and postseismic (airborne geodesy) crustal deformation. The multi-temporal interferometry is performed using the standard method for persistent scatterers (StaMPS/MTI software) applied to ERS1/2, ENVISAT and Sentinel SAR images, all from C-band dataset on descending and ascending orbits. The GPS velocities are modeled and re-interpreted from previous works in order to fit the tectonic block sub-division and related major faulting geometry. The seismicity rate and associated major earthquakes such as the El Asnam in 10/10/1980 (Mw 7.1) and Zemmouri-Boumerdes in 05/21/2003 (Mw 6.8) mark the seismotectonic characteristics of the Tell Atlas. The achieved data analysis and results of the joint InSAR, GPS and seismotectonics reveal that large areas with active deformation undergo uplifting and shortening with a consistent tectonic, geodetic and seismicity rate ranging between 2 and 3 mm/yr. |
