http://hdl.handle.net/10174/649 Sat, 04 Apr 2026 02:54:51 GMT 2026-04-04T02:54:51Z http://hdl.handle.net/10174/32045 Title: Surface Deformation Monitoring from SAR Interferometry for Seismic Hazard Assessment Around Major Active Faults: Case of Zemmouri Earthquake (Algeria) Authors: Aguemoune, S.; Ayadi, A.; Belhadj-Aissa, A.; Bezzeghoud, M. Editors: Meghraoui, M.; Banerjee, S.; Eshagh, M.; Chaminé, H. I.; Michard, A.; Sundararajan, N.; Hinzen, K-G.; Roure, F.; Maouche, S. Abstract: In seismogenic zones, geodetic campaigns are usually used to monitor the ground deformation. Nowadays, satellite imaging became a powerful tool to monitor surface deformation on very large areas using InSAR (Interferometry Synthetic Aperture Radar). To get reliable results, reducing errors became a real challenge. We recently proposed a new phase unwrapping procedure and a new technique to reduce atmospheric errors. These techniques were assembled to develop a new InSAR time series methods named ISBAS (Improved Small BAseline Subsets). We tested our procedure on Zemmouri (Algeria) seismogenic zone struck by an Mw 6.8 earthquake in 2003. Several SAR images from ENVISAT satellite were used in combination with data from MERIS tool embed- ded on the same satellite to monitor post-seismic deformation. Our analysis highlights the zones of signif- icant deformation due to not only post-seismic seismic movement, but also to other anthropogenic origin. This kind of studies can really help to better assess the seismic hazard around major active fault such as that of Zemmouri and on other active sources that could generates strong seismic events. Thu, 31 Mar 2022 23:00:00 GMT http://hdl.handle.net/10174/32045 2022-03-31T23:00:00Z http://hdl.handle.net/10174/32044 Title: High-density Seismic Network for Monitoring Alentejo Region (Portugal) and Mitidja Basin Region (Algeria) Authors: Manso, M.; Bezzeghoud, M.; Borges, J. F.; Caldeira, B.; Fontiela, J.; Ayadi, A. Editors: Meghraoui, M.; Banerjee, S.; Eshagh, M.; Chaminé, H. I.; Michard, A.; Sundararajan, N.; Hinzen, K-G.; Roure, F.; Maouche, S. Abstract: The seismic sensor network Alentejo (SSN-Alentejo) developed by the Earth Sciences Institute (Instituto de Ciências da Terra, University of Évora) brings the largest high-density seismic sensor network ever deployed in Portugal. This novel network aims to improve the characterization of seismic activity in the region, through a high-resolution mapping of seismic clusters and known faults. Over the next two years, SSN-Alentejo will deploy a monitoring network of 300 sensors, combining high-sensitive sensors with low-cost sensors. SSN-Alentejo augments existing sensing and monitoring capabilities, enabling the opportunity to observe, for the first time in Portuguese territory, live seismic activity in high resolution. Moreover, seismogenic zones such as the Mitidja or Chleff basins in Algeria will also benefit from having a high-density network. Thu, 31 Mar 2022 23:00:00 GMT http://hdl.handle.net/10174/32044 2022-03-31T23:00:00Z http://hdl.handle.net/10174/32040 Title: Algerian’s Seismic Catalogue Completeness from Historical Instrumental Monitoring, Archeoseismological and Paleoseismological Studies. Authors: Ayadi, A.; Ousadou, F.; Roumane, K.; Harbi, A.; Maouche, S.; Bezzeghoud, M.; Meghraoui, M. Editors: Meghraoui, M.; Banerjee, S.; Eshagh, M.; Chaminé, H. I.; Michard, A.; Sundararajan, N.; Hinzen, K-G.; Roure, F.; Maouche, A. Abstract: For any seismic hazard study, a reliable, homogenized and complete seismic catalogue is required. The Algerian seismicity catalogue has been recently updated by retrieving and reappraising many historical events. The Algerian seismic network has also been densified up to about 80 seismic stations covering the Tell Atlas which is the most active area of northern Algeria for monitoring of the seismic activity reducing the magnitude threshold. Recently, we have launched archeoseismological studies to retrieve past strong earthquakes that have affected Roman sites located along the Tell Atlas. Here, we proceed with tectonic investigations around selected sites where significant observed damage was identified. On the other hand, paleoseismological investigations were con- ducted along the El Asnam fault (now Chlef) following the large Ms 7.3 earthquake of 1980. Paleoseismic studies combined with archeoseismological results provide the dating of past earthquakes and contribute to the com- pleteness of the seismicity catalogue. Tue, 01 Mar 2022 00:00:00 GMT http://hdl.handle.net/10174/32040 2022-03-01T00:00:00Z http://hdl.handle.net/10174/27239 Title: Changing the Topology of Electronic Systems Through Interactions or Disorder Authors: Araújo, Miguel; Castro, Eduardo; Sacramento, Pedro Editors: Huixia, Luo Abstract: Recent work on the influence of interactions or disorder on the topological properties of insulators is reviewed. We show that a purely local interaction can cause topological transitions by renormalizing kinetic energy terms alone, without phase transitions associated with order parameters. Disorder is also a mean of changing the topology of Chern insulators, as it localizes every state except for those carrying the topological invariant. With increasing disorder, states with opposite topological invariant meet and annihilate. But considering the sub-lattice degree of freedom, Chern insulators may evade localization: an anomalous Hall metal may be stabilized with strong disorder in one sublattice, while the disorder in the other sublattice remains below some critical value. Also, a ferromagnetically ordered chain of magnetic impurities on conventional singlet superconductors with spin-orbit interaction induces topological Majorana modes at the ends of the chain. A ferromagnetic chain at the surface of a superconductor with spin–orbit coupling may eliminate the helical edge states of a finite system, while localized zero modes at the edges of the chain appear. Increasing the impurity density from a magnetic chain to an island produces a finite Chern number. At half-filling small concentrations may already induce chiral modes. Tue, 12 Mar 2019 00:00:00 GMT http://hdl.handle.net/10174/27239 2019-03-12T00:00:00Z