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A compilation of potential sources for earthquakes larger than M 5.5 in Italy and surrounding areas


Composite Seismogenic Sources

The Composite Seismogenic Sources (formerly Seismogenic Areas) are based on geological and geophysical data and are characterized by geometric (strike, dip, width, depth) and kinematic (rake) parameters.
A Composite Seismogenic Source is essentially an inferred structure based on regional surface and subsurface geological data that are exploited well beyond the simple identification of active faults or youthful tectonic features. However, the length of the expected earthquake ruptures is poorly defined or unknown; hence, a typical Composite Seismogenic Source spans an unspecified number of Individual Seismogenic Sources. As a result, sources of this category are not assumed to be capable of a specific-size earthquake, but the analysis of the tectonic moment rate and earthquake catalogs can help estimate their seismic potential. When available, their description can be augmented by fault scarp or fold axis data (usually structural features with documented Late Pleistocene - Holocene activity).

As opposed to the Individual Seismogenic Sources, this category of sources was conceived to achieve completeness of the record of potential earthquake sources, although this may imply a smaller accuracy in their description. Composite Seismogenic Sources can thus contribute to developing regional probabilistic hazard analyses and investigating large-scale geodynamic processes in conjunction with seismicity and modern strain data.

Similarly to the other categories of DISS sources, each Composite Seismogenic Source is identified by the code CCCS###, where:
  • CC is the two-letter ISO 3166-1 code for names of officially recognized countries;
  • CS identifies specifically the Composite Seismogenic Sources;
  • ### is an ordinal between 1 and 999 (including leading zeroes).
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