The Holocene activity of the Rodià Fault, Central Greece

One of the major Middle-Late Quaternary faults separating the Tyrnavos Basin from the Gonnoi Horst, Thessaly, Central Greece, has been investigated following a multidisciplinary approach. In particular, the Late Pleistocene and Holocene seismogenic activity of the fault has been documented by (i) morphological data, such as triangular facets and a set of tectonic scarps in Late Quaternary deposits; (ii) structural data, such as tilted sediments against normal faults and a thick shear zone along the major Quaternary-bedrock contact; both features affecting Late Pleistocene-Early Holocene deposits; (iii) palaeoseismological data showing a morphogenic event in Middle-Late Holocene alluvial sediments. This approach enabled the characterisation of the most recent seismic event along the Rodià Fault that occurred at 2-3 ka BP. Based on the collected data and according to published empirical relationships among different seismotectonic parameters, it is possible to estimate a magnitude of ca. 6.4 for the last event. The seismic hazard induced by this tectonic structure for Northern Thessaly is analysed, while the seismic risk for the area and particularly for Larissa, the third major town of Greece, is also discussed.