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North Africa is one of the most earthquake-prone areas of the Mediterranean. Many devastating earthquakes, some of them tsunami-triggering, inflicted heavy loss of life and considerable economic damage to the region. In order to mitigate the destructive impact of the earthquakes, the regional seismic hazard in North Africa is assessed using the neo-deterministic, multi-scenario methodology (NDSHA) based on the computation of synthetic seismograms, using the modal summation technique, at a regular grid of 0.2 × 0.2°. This is the first study aimed at producing NDSHA maps of North Africa including five countries: Morocco, Algeria, Tunisia, Libya, and Egypt. The key input data for the NDSHA algorithm are earthquake sources, seismotectonic zonation, and structural models. In the preparation of the input data, it has been really important to go beyond the national borders and to adopt a coherent strategy all over the area. Thanks to the collaborative efforts of the teams involved, it has been possible to properly merge the earthquake catalogues available for each country to define with homogeneous criteria the seismogenic zones, the characteristic focal mechanism associated with each of them, and the structural models used to model wave propagation from the sources to the sites. As a result, reliable seismic hazard maps are produced in terms of maximum displacement ( D), maximum velocity ( V), and design ground acceleration. [ABSTRACT FROM AUTHOR]

The modal summation method to compute synthetic seismograms is applied to carry out a study of seismic zonation in Albania.From a seismotectonic synthesis and the available earthquake data, eight seismogenic zones are defined and for each of them, a characteristic focal mechanism is selected. A new seismic velocity model is used in the computations and is constructed on the basis of previous studies. Correlation relations between the maximum intensity values observed and the ground motion parameters obtained from this procedure are derived.The distribution of the calculated values of displacement, velocity and acceleration, will contribute to the quality of anti-seismic design practice in Albania and to the mitigation of earthquake consequences. [Copyright &y& Elsevier]

Many devastating earthquakes inflicted heavy casualties and property losses in the seismically active China Seismic Experimental Site area (CSES: 97.5° ~ 105.5°E, 21° ~ 32°N). We performed a first-order seismic zoning based on Neo-deterministic Seismic Hazard Assessment (NDSHA) in the study area delimited by 94° ~ 108°E and 19° ~ 35°N, containing the South-East margin of the Tibetan Plateau and the Sichuan-Yunnan region. The seismic hazard is expressed by maps of peak ground displacement (PGD), peak ground velocity (PGV) and design ground acceleration (DGA) values, extracted from synthetic seismograms computed at a regional scale and mapped on a regular grid of 0.2° × 0.2° over the study area. For the computation of synthetic seismograms, we considered and updated all the available geophysical-geological-tectonic information, including historical and instrumental earthquake catalogues, seismogenic zones, seismogenic nodes, focal mechanisms, and geophysical structural models. We tested the performance of our assessments with available data (i.e., after the Great Wenchuan (2008, May 12th, M s = 8.0) and Lushan (2013, April 20th, M s = 7.0) earthquakes) and verified the negligible influence of large events located "far" from the study area. The results indicate the high seismic hazard of the region, with a particular attention (i.e., where DGA > 0.6 g) to the areas located around the main fault zones, e.g., the Longmenshan, Anninghe and Zemuhe Fault Zones. These first-order NDSHA zoning findings may serve as a knowledge basis to support both large- to mid-range preparedness actions and (multi-scenario) site-specific studies. • Neo-Deterministic Seismic Hazard Assessment maps for China Seismic Experimental Site. • The "predictive" power of NDSHA before and after the 2008 M 8.0 Wenchuan earthquake. • Validation of NDSHA against instrumental records of the 2008 M 8.0 Wenchuan earthquake. • Formulation of seismic hazard maps derived from M design for efficient practical applications. [ABSTRACT FROM AUTHOR]