ALBERT

Description: The seismicity data file used for this study is represented by the earthquake catalogue CENEC for Europe north of 44°N (Grünthal et al. 2009a). This paper describes in detail how this homogeneous data file in terms of moment magnitudes Mw (with Mw greater than 3.5) has been derived. The degree of harmonization achieved in CENEC is quantitatively analysed in Grünthal et al. (2009b).

Description: The purpose of this study is to refine the probabilistic seismic hazard assessment for Vanuatu. The analysis is complicated by inconsistencies of the global and local data for the investigated region and systematic inadequacies of the attenuation relation available. An additional aspect in the field of which more research would be desirable is the de-clustering algorithm for the identification of dependent earthquakes. In order to quantify the inevitable uncertainties associated with our results, we used a Logic Tree approach. The report is subdivided into seven chapters. Chapter 2 summarises the geology and tectonic setting of the Vanuatu island arc. Prior scientific investigations will be sketched briefly and to the degree to which they are relevant for our further considerations. The consecutive Chapter 3 describes the different data sources used for the calculations. Together, the local earthquake catalogue provided by the IRD (Institut de Recherche pour le D´eveloppement) and the global catalogues constitute a comprehensive data base for the region. The homogenisation of different catalogues required the conversion of magnitudes through maximum likelihood regressions. Chapter 4 gives a brief overview over the methodological concept applied. The implementation of the Cornell methodology involves two key steps: The first step is to construct a seismicity model (Chapter 5) including the definition of source zones and seismicity parameters characterising the level and type of activity in the respective zone. The second step is to determine an appropriate attenuation relation for the earthquake-generated ground motion in dependence of magnitude and distance. Chapter 6 compares several attenuation relations from the recent geophysical literature. We argue that the modeling of attenuation is the weakest link in this analysis and the major source of uncertainty. The new seismic hazard maps are presented and discussed in Chapter 7. The map that we consider to be the most relevant is also shown on the inner title page of this report. Our findings indicate that the seismic hazard in Vanuatu has been underestimated by prior assessments such as the Global Seismic Hazard Assessment Programme GSHAP (cf. Fig. 1.1).

Description: The paper consists of two main elements: (1) the creation of a harmonized seismicity data file for the eastern Mediterranean area and the generation of a classical timeindependent PSHA, and (2) the extension of the earthquake model of the timeindependent approach to a newly developed time‐dependent PSHA and the comparison with the results of (1).

Description: In diesem Bericht werden die Ergebnisse der neuen Generation probabilistischer seismischer Gefährdungseinschätzungen (PSHA) in der Version von 2007 vorgestellt. Die Parametrisierung der Berechnungsergebnisse erfolgt in Form spektraler Antwort- Beschleunigungen und der Spitzenbodenbeschleunigungen (PGA). Bezüglich ersterer stellen sie eine Neuheit für die Bundesrepublik Deutschland dar, während letztere die PGA-Karten von 1997 ersetzen.

Description: A Databank was created using data from 25 local catalogues and 30 special studies of earthquakes in central, northern and northwestern Europe. Event types were discriminated, fake events and duplets eliminated, and different magnitudes and intensities converted to Mw. The conversions require the establishment of regression equations. The Catalogue contains tectonic events from the Databank within the area 44°N-72°N, 25°W-32°E and the time period 1300-1993 which have Mw magnitudes of 3.50 and larger. The area is covered by different polygons. Within each polygon only data from one or a small number of the local catalogues, supplemented by data from special studies, enter the Catalogue. If there are two or more such catalogues or studies providing a solution for an event, a priority algorithm selects one entry for the Catalogue. Then Mw is calculated from one of the magnitude types, or from macroseismic data, given by the selected entry according to another priority scheme. The origin time, location, Mw magnitude and reference are specified for each entry of the Catalogue. So is the epicentral intensity, I0, if provided by the original source. Following these criteria, a total of about 5,000 earthquakes constitute the Catalogue. Although originally derived for the purpose of seismic hazard calculation within GSHAP, the Catalogue provides a data base for many types of seismicity and seismic hazard studies.