25 years of satellite InSAR monitoring of ground instability and coastal geohazards in the archaeological site of Capo Colonna, Italy
2016
For centuries the promontory of Capo Colonna in Calabria region, southern Italy, experienced land subsidence and
coastline retreat to an extent that the archaeological ruins of the ancient Greek sanctuary are currently under threat of
cliff failure, toppling and irreversible loss. Gas extraction in nearby wells is a further anthropogenic element to account
for at the regional scale. Exploiting an unprecedented satellite Synthetic Aperture Radar (SAR) time series including
ERS-1/2, ENVISAT, TerraSAR-X, COSMO-SkyMed and Sentinel-1A data stacks acquired between 1992 and 2016, this
paper presents the first and most complete Interferometric SAR (InSAR) baseline assessment of land subsidence and
coastal processes affecting Capo Colonna. We analyse the regional displacement trends, the correlation between vertical
displacements with gas extraction volumes, the impact on stability of the archaeological heritage, and the coastal
geohazard susceptibility. In the last 25 years, the land has subsided uninterruptedly, with highest annual line-of-sight
deformation rates ranging between -15 and -20 mm/year in 2011-2014. The installation of 40 pairs of corner reflectors
along the northern coastline and within the archaeological park resulted in an improved imaging capability and higher
density of measurement points. This proved to be beneficial for the ground stability assessment of recent archaeological
excavations, in an area where field surveying in November 2015 highlighted new events of cliff failure. The conceptual
model developed suggests that combining InSAR results, geomorphological assessments and inventorying of wave-storms
will contribute to unveil the complexity of coastal geohazards in Capo Colonna.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
14
References
8
Citations
NaN
KQI