Alluvial Fans at Cala Gonone (Sardinia), a Fast Deveoping Touristic Village: Origins, Hazards and Potential Risks [post]

Vincenzo Pascucci, I. Peter Martini, Stefano Andreucci
2022 unpublished
The study area of Cala Gonone in NE Sardinia (Italy) consists of a wide terraced re-entrance/valley crowned inland by carbonate hills and, near the coast bounded laterally and partly floored by thin basaltic lava lying over carbonate bedrock. In this re-entrance, several inland alluvial fans have developed, and a local ~ 30 m high, about 10 m wide (thick), 400 m long scarp body-remnant of semi-consolidated alluvial fan deposits is exposed along the coast. The touristic village of Cala Gonone
more » ... been rapidly expanding in these last few decades over the mid to lower parts of two coalescing alluvial fans and along the coastal marine scarp edge. The village thus became exposed to natural hazards such as sudden overland and creek floods and debris flows typical of alluvial fans, local rock falls, and to instability of the costal scarp due to wave erosion during extreme sea storms. As commonly occurring elsewhere and since antiquity, the risk perception of such events is low because of the centennial, millennial of longer recurrence. Such perception does not negate the hazards but a long event recurrence can be accepted as a reasonable risk for the human's activity in certain areas. However, serious consideration should be given to potential problems and plan and build for amelioration and defense. Many examples of what can occur and could be done exist from the careful safe-location of the ancient Roman villas to the recent disastrous cases where parts of ill-located villages have been destroyed by debris flows and floods along alluvial fans. The evidence of what did and could still happen in the Cala Gonone and similar other area is clearly imprinted on the landscape (geology, geomorphology, and with relative details in the stratigraphy as sedimentology of the deposits) and driven by climatic conditions and human activities.
doi:10.21203/ fatcat:fkrat4w2wjgudkrpvclc4m32vy