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International audience; The Mw 6.4 right-lateral Petrinja earthquake (2020, Croatia) is one of the largest continental earthquakes of central Europe for decades. The slip pattern of such events is usually difficult to retrieve with terrestrial geodesy due to limited monitoring means. This study takes advantage of a unique data set of dense measurements of coseismic displacement in the epicentral area, obtained by repeated measurements of benchmark networks designed for civilian purposes, and supplemented by far-field continuous GNSS measurements. Elastic modeling of these data shows two coseismic slip patches that extend over a 15 × 10 km rupture plane, locally reaching the surface, and that a right-lateral sub-parallel secondary fault in the central part of the rupture likely accommodated part of the coseismic deformation. This study demonstrates that rapid re-measurement of pre-existing civilian networks offers unique coseismic constrains in the near-field where InSAR or optical image correlation may decorrelate. more...

Acceso electrónico sólo desde el IGME, Landslides are one of the most widespread geohazards in Europe, producing significant social and economic impacts. Rapid population growth in urban areas throughout many countries in Europe and extreme climatic scenarios can considerably increase landslide risk in the near future. Variability exists between European countries in both the statutory treatment of landslide risk and the use of official assessment guidelines. This suggests that a European Landslides Directive that provides a common legal framework for dealing with landslides is necessary. With this long-term goal in mind, this work analyzes the landslide databases from the Geological Surveys of Europe focusing on their interoperability and completeness. The same landslide classification could be used for the 849,543 landslide records from the Geological Surveys, from which 36% are slides, 10% are falls, 20% are flows, 11% are complex slides, and 24% either remain unclassified or correspond to another typology. Most of them are mapped with the same symbol at a scale of 1:25,000 or greater, providing the necessary information to elaborate European-scale susceptibility maps for each landslide type. A landslide density map was produced for the available records from the Geological Surveys (LANDEN map) showing, for the first time, 210,544 km2 landslide-prone areas and 23,681 administrative areas where the Geological Surveys from Europe have recorded landslides. The comparison of this map with the European landslide susceptibility map (ELSUS 1000 v1) is successful for most of the territory (69.7%) showing certain variability between countries. This comparison also permitted the identification of 0.98 Mkm2 (28.9%) of landslide-susceptible areas without records from the Geological Surveys, which have been used to evaluate the landslide database completeness. The estimated completeness of the landslide databases (LDBs) from the Geological Surveys is 17%, varying between 1 and 55%. This variability is due to the different landslide strategies adopted by each country. In some of them, landslide mapping is systematic; others only record damaging landslides, whereas in others, landslide maps are only available for certain regions or local areas. Moreover, in most of the countries, LDBs from the Geological Surveys co-exist with others owned by a variety of public institutions producing LDBs at variable scales and formats. Hence, a greater coordination effort should be made by all the institutions working in landslide mapping to increase data integration and harmonization., Earth Observation and Geohazards Expert Group (EOEG), EuroGeoSurveys, the Geological Surveys of Europe, Bélgica, Geohazards InSAR Laboratory and Modeling Group, Instituto Geológico y Minero de España, España, Risk and Prevention Division, Bureau de Recherches Géologiques et Minières, Francia, Engineering Geology Department, Institute of Geology and Mineral Exploration, Grecia, GeoHazard team, Geological Institute of Romania, Rumanía, Geological Survey of Slovenia, Eslovenia, Croatian Geological Survey, Croacia, Italian Institute for Environmental Protection and Research, Geological Survey of Italy, Italia, Swiss Federal Office for the Environment, Suiza, Geological Survey of Austria, Austria, Polish Geological Institute, National Research Institute, Polonia, Geological Survey of Ireland, Irlanda, Czech Geological Survey, República Checa, Federal Institute for Geosciences and Natural Resources, Alemania, Geological Survey of Norway, Noruega, Cyprus Geological Survey, Chipre, Geological Survey of Sweden, Suecia, Institut Cartogràfic i Geològic de Catalunya, España, British Geological Survey, Reino Unido, Geological Survey of Slovakia, Eslovaquia, Geological Survey of Lithuania, Lituania, Federalni zavod za geologiju, Bosnia y Herzegovina, Geological Survey of Estonia, Estonia, Laboratório Nacional de Energia e Geologia, Portugal, Geological Survey of Hungary, Hungría, Norwegian Water and energy Directorate of Norway, Noruega more...