Using the EFEHR portal

This portal provides you with the ability to browse the results of the probabilistic seismic hazard assessment for the Euro-Mediterranean region. The hazard products result from a complex procedure and there are thus various ways of looking at the results.

The basic viewer functionality is the same for the hazard maps, curves, and spectra:

  1. Select a place of interest, either by double-clicking the map with the arrow tool, or by adding a site location (left upper box)
  2. select a hazard model. Only models with data available at the point of interest are displayed.
  3. select an intensity measurement type. Choices are PGA (peak ground acceleration), PGV (peak ground velocity), SA (spectral acceleration, with spectral period in corner brackets), and potentially others, depending on the model.
  4. select a site class (note that the options available may be different from the true soil conditions at your site of interest)
  5. select an aggregation type. Aggregation types describe how the selected values were derived from the set of single-branch results of a logic tree model. Typical choices are mean, median, and fractiles.