Sinkhole monitoring and early warning: an experimental application of ground-based interferometry

Emanuele Intrieri (a), Giovanni Gigli (a), Massimiliano Nocentini (a), Luca Lombardi (a), Francesco Mugnai (a), Francesco Fidolini (a), Lorenzo Dimase & Nicola Casagli (a)
(a) Department of Earth Sciences , University of Studies of Firenze, via La Pira 4, 50124, Firenze, Italy. E-mail: emanuele.intrieri@gmail.com

At Il Piano (Elba Island, Central Italy) 11 sinkhole events occurred on 9 different points on or close to a strategic road connecting Rio Marina to the rest of the island. In order to reduce the risk, a ground-based interferometric radar has been experimentally installed to detect possible precursor deformations of the ground. In this paper we present the results of a test simulating the occurrence of a sinkhole, which highlighted the criticalities of the method, and the successful prediction of a sinkhole event that could have endangered people travelling along the road. These experiences constitute a very important premise and confirm the possibility to measure precursor deformations even days before the opening of a sinkhole. This is due to the presence of a cover consisting in plastic material (clay, silt and even the street tar) that experiences a deformation before rupture as the sinkhole propagates from the bedrock.

early warning system, ground-based radar interferometry, karst, monitoring, sinkhole.