SHARE: European Seismic Hazard Maps

From the SHARE Consortium

Supported by the EU 7th Framework Program, the project SHARE (Seismic Hazard Harmonization for Europe) brought together leading scientists from 18 research institutions and 12 countries to homogeneously assess data and to harmonize methodologies to estimate seismic hazard throughout Europe, including Turkey. Over fifty researchers - seismologists, geologists, geodesists, historians, earthquake engineers, computer scientists, statisticians, and outreach specialists - formed the core team for the four year project, with more than 250 additional experts providing their expertise and data.

The project generated the first ever set of harmonized seismic hazard results and maps, characterizing the hazard and its uncertainty, to serve as input for risk assessment and earthquake resistant design for different applications, ranging from private homes to multi-story public buildings and critical infrastructures such as bridges or dams. Through the coordination at the European Union level, these hazard results will help to harmonize the next generation of national seismic hazard assessments and harmonize the implementation of the European seismic building code (EuroCode8). The SHARE results form the basis for risk assessment and for the formulation of policies for its mitigation. SHARE however does not replace the existing national design regulations and seismic provisions, which should be obeyed for today's design and construction of buildings.

The SHARE data collection and hazard results will in addition accelerate the generation of new scientific and technical knowledge and data to further improve seismic hazard assessment in Europe.

European Seismic Hazard Maps

The European Seismic Hazard Maps are based on a time-independent, probabilistic approach. Three different earthquake rate models have been assembled from available data, reflecting the state-of-the art knowledge on
  • past moderate to large earthquakes, as documented by their damaging effects through history and since 1980 with modern instrumental seismic networks, all combined in a single European Earthquake Catalogue (SHEEC),
  • fault structures and subduction zone models, included in the new European Database of Seismogenic Faults (EDSF),
  • and the rate of deformation of the Earth crust as observed by global positioning systems.
The models are then combined with the ground motion prediction equations (GMPE) selected through an expert elicitation process and calibrated for the SHARE strong ground motion databank.  More than 300 maps have been produced, spanning spectral ordinates from PGA to 10 seconds and exceedance probabilities ranging from 10-1 to 10-4 yearly probabilities. The hazard values are referenced to a rock velocity of Vs30=800m/s and were computed using the OpenQuake hazard engine developed within the Global Earthquake Model (GEM) initiative. Hazard curves, uniform hazard spectra (UHS) and disaggregation results are computed for more than 120,000 sites on-land within Europe and Turkey, spaced at about 10km from each other.

The above European Seismic Hazard Map displays the Peak Ground Acceleration (PGA) expected to be reached or exceeded with a 10% probability in 50 years, or to return on average every 475 years. Green colour indicates comparatively low hazard values of PGA below 0.1g, yellow to orange colours depict moderate hazard between 0.1-to-0.25g and red colours identify high hazard areas with PGA of more than 0.25.

Online Data Access

The SHARE products, input data and results, are available and documented through the web portal of the European Facility for Earthquake Hazard and Risk (EFEHR): 

Whenever you use SHARE data, please quote:

D. Giardini, J. Woessner, L. Danciu, H. Crowley, F. Cotton, G. Gruenthal, R. Pinho, G. Valensise, S. Akkar, R. Arvidsson, R. Basili, T. Cameelbeck, A. Campos-Costa, J. Douglas, M. B. Demircioglu, M. Erdik, J. Fonseca, B. Glavatovic, C. Lindholm, K. Makropoulos, F. Meletti, R. Musson, K. Pitilakis, K. Sesetyan, D. Stromeyer, M. Stucchi, A. Rovida, Seismic Hazard Harmonization in Europe (SHARE): Online Data Resource, doi:10.12686/SED-00000001-SHARE, 2013.

The SHARE Perspective

The SHARE results will remain accessible in future through the portal of the European Facility of Earthquake Hazard and Risk located at the Swiss Seismological Service / ETH Zurich.

Domenico Giardini                         Jochen Woessner

Coordinator                                    Project Manager

and the SHARE-consortium