I movimenti gravitativi profondi della zona di Chioso (Val di Magra): aspetti geologici e geomorfologici e influenza sull’ambiente antropico

The deep-seated gravitational movement of the Chioso area (Magra Valley, North-Western Tuscany): geological and geomorphological aspects and influence on the anthropic environment

Abstract

Chioso is an ancient small village in North-western Tuscany, close to the watershed between Magra Valley and Vara Valley (Northern Apennines); many active and dormant landslides and deep seated gravitational slope deformations make this territory prone to a very severe landslide hazard, that affects built-up areas and infrastructures. In this area, a geological and geomorphological survey was carried out in order to obtain a good knowledge of mass movement types and activity and of their relations to the geological structure, characterised by competent rocks (calcareous-marly flysch) overlying incompetent argillitic rocks. Historic researches have been conducted, in order to know how the slope instability influenced anthropic activities and environment: newspapers, public administrations, libraries and parishes have been consulted and many persons have been interviewed. In this way, a centuries old and recurrent activity of mass movements was testified, dating back to at least the 16^th century and extending to the present. Today, Chioso suffers from heavy damage for landslides; it is in an advanced state of neglect so that its historic heritage may be lost.