Historical, archaeoseismic, paleoseismological and active tectonics markers in the Avola Vecchia area (southern Sicily)

Coeval sources describe with certainty a landslide triggered by the 11 January 1693 Sicilian earthquake near Avola Vecchia. The landslide occurred west of the town, at Mt Ginisi, along the Miranda river, which was the economic and productive focus of the territory hosting five mills. The landslide destroyed three mills and dammed the river. Near Avola Vecchia, at Mt Aquilone, we have recognized several fractures in rock masses as well as in anthropogenic caves (the so-called cave houses) and oven-shaped tombs, dating back to the Byzantine period and Sicels’ age respectively. The mesostructural analysis of the rock masses showed that fractures are mainly classifiable as joints and that some of them are due to the tectonic stress field confirming that in southern Sicily a WNW - ESE extensional regime is still active. Some fractures are due to seismic shaking and slope gravity effects, suggesting that several earthquakes have affected the area