Wasowski J, Bovenga F, Nutricato R, Conte D, Refice A, Graniczny M, Kowalski Z., 2009, Spatial distribution of subsidence in the Wieliczka Salt Mine area as detected through satellite interferometry, Przeglad Geologiczny 57 (2009): 164–172.,
URL: http://www.cnr.it/prodotto/i/67065

The paper presents the use of the Persistent Scatterers Interferometry (PSI) Synthetic Aperture Radar (SAR) data to determine magnitude of subsidence in area of the town ofWieliczka. The town is home to a unique salt mine, over 700 years old, one of the best known tourist attractions in Poland. Each year the mine is visited by about 1 million tourists from all over the world and in 1978 UNESCO placed it on its first International List of theWorld Cultural and Natural Heritage. There is direct evidence that the mining has been influencing stability of ground and buildings in the town, which is located above the mine. The application of the PSI SPINUA technique made it possible to identify large number of radar targets (with density exceeding 100 PS/km2), suitable for monitoring ground motion in the Wieliczka area. The results show continuous subsidence with average annual movements ranging from a few millimeter per year to 24 mm/yr in the period 1992-2000. The detected subsiding zone very well corresponds to the extent of the underground salt mine. There are also indications of possible connections between the mine-induced subsidence and the presence of the old large landslides occurring on the north-facing slopes south of the Wieliczka Salt Mine.

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