In this work,

In the last few years, several advances have been made in the use of radar images to detect, map and monitor ground deformations. DInSAR (Differential Synthetic Aperture Radar Interferometry) and A-DInSAR/PSI (Advanced DInSAR/Persistent Scatterers Interferometry) technologies have been successfully applied in the study of deformation phenomena induced by, for example, active tectonics, volcanic activity, ground water exploitation, mining, and landslides, both at local and regional scales. In this paper, the existing European Space Agency (ESA) archives (acquired as part of the FP7-DORIS project), which were collected by the ERS-1/2 and ENVISAT satellites operating in the microwave C-band, were analyzed and exploited to understand the dynamics of landslide and subsidence phenomena. In particular, this paper presents the results obtained as part of the FP7-DORIS project to demonstrate that the full exploitation of very long deformation time series (more than 15 years) can play a key role in understanding the dynamics of natural and human-induced hazards.

No abstract

The article contains results obtained from realization of the Polish and Lithuanian Baltic case study within the EU -FP 7 SubCoast project, which one of the primary aims was analysis of vertical ground movements, potentially causing geohazards in the coastal areas. To reach this goal Interferometric Synthetic Aperture Radar (InSAR) data were obtained. For the Polish and Lithuanian Baltic coast ERS archive radar data were processed in order to provide Permanent Scatterer (PSInSAR, PSI) results that were then used to create the new innovative productDynamic DEM (DDEM). The deformation model defined by the SubCoast project normally needs to be created by merging InSAR, satellite navigation (GNSS), optical leveling and/or gravimetry measurements. Elaboration of DDEM enables more effective comparison between PS and tectonic features. Comparison of PS time series with groundwater changes shows a direct correlation, confirming impact of groundwater on subsidence or uplift of the ground surface. The results of the geological interpretation demonstrated that the examples of movements detected by PSI include subsidence linked to deformation of engineering constructions, compaction of organic or weak soils, and eolian accumulation or deflation processes of the sand dunes. For the Polish and Lithuanian coasts most of the area proved to be stable, nevertheless some local deviations up to -15 mm per year of movement were found.

Groundwater monitoring in the PolishLithuanian cross-border area was launched in 1994, utilizing 24 monitoring stations. Of these, 20 are installed in aquifers in Quaternary tills, which are the main source of fresh water for centralized use and single households. Hydro-chemical sampling has been performed twice a year (spring and autumn) over a seven-year period, with determination of main chemical compounds. Hydrochemical differences on both sides of the border appear to be related to the type of land use. The groundwater quality on the Lithuanian side may have been influenced by anthropogenic factors operating prior to 1991 in the Soviet-type collective farms. The main trends over the monitoring period involve increase in SO 4 2+ and Cl -ions on both sides of the border. The data demonstrate the importance of cross-border monitoring and exemplify groundwater chemistry as a direct geoindicator of the state of the environment.