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[EN] The SAR Interferometry techniques, Persistent Scatterer Interferometry (PSI) among them, are nowadays known as important tools for monitoring Earth surface movements. Several regional and national Ground Motion Services based on PSI already exist. Moreover, since 2022 the European Ground Motion Service will be operational and will annually provide an updated displacement map over the whole Europe. This will suppose a big amount of ground displacement measurements along the European territory. For each measurement EGMS will provide the annual velocity and the time series of deformation covering the period 2014 to one year prior to each delivery. In this context, it will be more and more necessary having tools to ease the management, analysis, and interpretation, of those wide areas and huge amount of data. We present here a first step in this direction: the ADATools are a set of tools to automatically have secondary, and more operational, products derived from a PSI map. Starting from a fast extraction of the most significant Active Deformation Areas (ADA), with the ADAFinder tool, then we can have a preliminary classification of the most probable phenomena (landslides, subsidence, settlements, or sinkholes) that is behind the detected movement, with the ADAClassifier tool. Moreover, LOS2hv tool allows to derive the horizontal (east-west) and vertical components of the movement in case we have maps of ascending and descending geometries. Finally, it is presented a product that analyzes the local displacement gradients to generate potential damage maps in urban areas. The tools will be presented thorough some results obtained on an area of the Granada County with the use of Sentinel-1 data. All the results have been achieved within the framework of the Riskcoast Project (financed by the Interreg Sudoe Program through the European Regional Development Fund, ERDF)., This work was mainly supported by the European Regional Development Fund (ERDF) through the project “RISKCOAST” (SOE3/P4/E0868) of the Interreg SUDOE Programme.

The InSAR technique has been proved to be a powerful tool in order to detect, monitoring and analyse movements related to geological phenomena. Its application ranges from regional/national scale to a very detailed scale, up to a single building analysis. Moreover, since 2014, the free and constant availability of Sentinel-1 data has been helping the tendency of using more and more this technique in the institutional risk management activities. Many European and national projects have been financed in order to investigate and improve the processing performances and broaden the operational use and application of the results. In this work, we present the first results developed in the framework of the project Riskcoast (SOE3/P4/E0868) over an area of around 4 km 2 in Andalucía (Spain), including the city and the coast of Granada. Riskcoast has been funded by the Interreg Sudoe Programme through the European Regional Development Fund (ERDF). The presented work is as an example of multi scale (medium to large) application of InSAR for geohazard applications. The velocity map including the estimation of the displacement time series have been produced over the whole area by processing 139 radar images of the Sentinel-1 (A and B). Starting from those results a rapid and semi-automatic extraction of the most significant active displacement areas (ADA) has been performed. Then, after a classification of the detected areas, a more detailed analysis has been done over some selected costal landslides. Over those landslides a damage mapping has been generated based on field surveys, and then analysed together with the spatial gradient of displacement derived by the InSAR results. The Riskcoast project will be introduced and the first results presented. Powered by TCPDF

International audience; The long-term Pressure-Temperature-time-deformation (P-T-t-d) evolution of the internal zones of orogens results from complex interactions between the subducting lithosphere, the overriding plate and the intervening asthenosphere. 2-D numerical models successfully reproduce natural P-T-t-d paths, but most orogens are non-cylindrical and the situation is far more complex due to 3-D pre-orogenic inheritance and 3-D subduction dynamics. The Mediterranean orogens are intrinsically non-cylindrical. Their 3-D geometry results from the complex shape of the Eurasian and African margins before convergence and from the dynamics of slab retreat and tearing leading to strongly arcuate belts. More than many other segments, the Betic-Rif belt is archetypal of this behavior. A synthesis of the tectonometamorphic evolution of the Internal Zones, also based on recent findings by our group in the framework of the Orogen Project (Alboran domain, including the Alpujárride-Sebtide and Nevado-Filábride complexes) shows the relations in space and time between tectonic and P-T evolutions. The reinterpretation of the contact between peridotite massifs and Mesozoic sediments as an extensional detachment leads to a discussion of the geodynamic setting and timing of mantle exhumation. Based on new 40Ar/39Ar ages in the Alpujárride-Sebtide complex and a discussion of published ages in the Nevado-Filábride complex, we conclude that the age of the HP-LT metamorphism is Eocene in all complexes. A first-order observation is the contrast between the well-preserved Eocene HP-LT blueschists-facies rocks of the eastern Alpujárride-Sebtide Complex and the younger HT-LP conditions reaching partial meltingrecorded in the Western Alpujárride. We propose a model where the large longitudinal variations in the P-T evolution are mainly due to (i) differences in the timing of subduction and exhumation, (ii) the nature of the subducting lithosphere and (iii) a major change in subduction dynamics at ~20 Ma associated with a slab-tearing event. The clustering of radiometric ages obtained with different methods around 20 Ma results from a regional exhumation episode coeval with slab tearing, westward migration of the trench, back-arc extension and thrusting of the whole orogen onto the African and Iberian margins.; L’évolution pressure-température-temps-déformation (P-T-t-d) des zones internes des orogènes résulte d’interactions complexes entre la lithosphère subduite, la plaque chevauchante et le manteau asthénosphérique. Les modèles numériques 2-D reproduisent assez bien les chemins P-T-t-d, mais les orogènes sont rarement cylindriques. L’héritage de la géométrie 3-D pré-orogénique et la dynamique 3-D de subduction rendent en effet la situation souvent plus complexe. Les orogènes méditerranéens sont intrinsèquement non-cylindriques parce que la géométrie des marges africaines et eurasiennes avant la collision était également non-cylindrique et parce que les panneaux lithosphériques en subduction ont changé de forme pendant le recul des fosses. Ils sont devenus plus étroits à la suite d’une série déchirures qui ont conduit à la formation d’arcs fortement pincés. L’orogène bético-rifain est emblématique de ce comportement, plus que tout autre segment. Une synthèse de l’évolution tectonométamorphique des zones internes de cet orogène, en partie basée sur des observations récentes faites par notre groupe dans le cadre du programme Orogen, dans le Domaine d’Alboran (incluant les nappes des Alpujárride-Sebtide et des Nevado-Filábride) montre les relations dans l’espace et le temps entre la éformation et l’évolution P-T. Une réinterprétation du contact entre les massifs péridotitiques et les sédiments carbonatés mésozoïques dans la région de Ronda conduit à une discussion sur le calendrier et le mécanisme de l’exhumation du manteau. Nous montrons que l’âge du métamorphisme de subduction est partout éocène en nous appuyant sur de nouveaux âges 40Ar/39Ar dans les Alpujárride-Sebtide et sur une discussion des âges publiés dans les Nevado-Filábride. Une observation de premier ordre est le contraste marqué entre les unités à paragenèses de HP-BT bien préservées des AlpujárrideSebtide orientales et centrales et les unités affectées par un métamorphisme plus jeune de HTLP atteignant les conditions de l’anatexie dans l’ouest des Alpujárride-Sebtide. Nous proposons un modèle où les variations longitudinales de la forme des conditions P-T résultent principalement de (i) différents calendriers de la subduction et de l’exhumation, (ii) la nature de la lithosphère subduite et (iii) un changement majeur de la dynamique de subduction il y a environ 20 Ma, associé à une déchirure du panneau plongeant. Le regroupement des âges radiométriques obtenus par différentes méthodes autour de 20 Ma dans toute la région résulte d’un épisode régional d’exhumation associé à la déchirure du panneau plongeant, la migration de la fosse vers l’ouest, l’extension arrière-arc et le chevauchement de l’ensemble de l’orogène sur les marges africaine et ibérique.