Becker-Heidmann, P., Reicherter, K. (2003): Complementing the earthquake history of Andalusia (Spain) by 14C dating of paleosols. 18th International Radiocarbon Conference. Wellington, New Zealand. Poster
The seismicity of southern Spain during the Holocene is characterized by frequent moderate to strong earthquakes distributed along several active faults in the Betic Cordilleras.
Seismic data have been recorded routinely only after one of the most destructive earthquakes in Spain which occurred at December 25, 1884, with its epicenter near the village Arenas del Rey.
For less frequently occurring seismic events of a magnitude >5.5, prior to that date, only few doubtful historical descriptions are available.
Along major fault systems in Andalusia, we found profiles with several stratified paleosols, preserved in the hanging walls of faults.
By radiocarbon dating of disturbed displaced and undisturbed soil layers, together with paleoseismic and neotectonic studies of the surface ruptures, we were able to gain missing dates of the earthquake history of this region.
We identifed two further Holocene (last 9.000 years) earthquake events with magnitude > 6 besides the one of 1884 along the fault through Ventas de Zaffaraya and Llanos de la Donna.
The obtained 14C dates fit well to the Richter-Gutenberg relation between frequency and magnitude of seismicity for the Granada region, which was established by the data of Morales et al. (1996) for frequently occurring recent small earthquakes and the strong Arenas del Rey event.
This implies recurrence rates of strong earthquakes in the order of 2.000.-3.000 years along that individual fault.