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On the application of SAR interferometry to geomorphological studies: estimation of landform attributes and mass movements 总被引：9，自引：0，他引：9
Filippo Catani Paolo Farina Sandro Moretti Giovanni Nico Tazio Strozzi 《Geomorphology》2005,66(1-4):119
This paper presents two examples of application of Synthetic Aperture Radar (SAR) interferometry (InSAR) to typical geomorphological problems. The principles of InSAR are introduced, taking care to clarify the limits and the potential of this technique for geomorphological studies. The application of InSAR to the quantification of landform attributes such as the slope and to the estimation of landform variations is investigated. Two case studies are presented. A first case study focuses on the problem of measuring landform attributes by interferometric SAR data. The interferometric result is compared with the corresponding one obtained by a Digital Elevation Model (DEM). In the second case study, the use of InSAR for the estimation of landform variations caused by a landslide is detailed. 相似文献
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DInSAR analysis of ALOS PALSAR images for the assessment of very slow landslides: the Tena Valley case study 总被引：2，自引：2，他引：0
Juan Carlos García-Davalillo Gerardo Herrera Davide Notti Tazio Strozzi Inmaculada Álvarez-Fernández 《Landslides》2014,11(2):225-246
In this work we analyse the performance of advanced land observing satellite (ALOS) phased array type L-band syntetic aperture radar (PALSAR) images for mapping and monitoring of very slow landslides using conventional differential interferometry in the Tena Valley (Central Pyrenees, Spain). These results are compared with those retrieved in previous works where multi-band advanced differential interferometric synthetic aperture radar (DInSAR) analysis was performed for the same area using PSI techniques. The study area is largely underlain by slates (ca. 80 %) where large deep-seated very slow earth flows are dominant. The results reveal that DInSAR analysis is able to measure displacements of landslides with a greater spatial coverage than PSI analysis, but for a lower amount of them (nine against 51). Overall, the combination of the DInSAR and multi-band PSI analysis permitted to map and monitor 68 % of the landslides in Tena Valley. From this amount, 63 landslides are considered as active. The main advantage of DInSAR with respect to PSI analysis is the capability to detect faster movements (up to 145 cm?year?1) derived from the 46 days interferograms. That is the case of Sextas and La Selva landslides where an acceleration of the moving mass was measured after intense rainfall periods producing major damages to linear infrastructures. The combination of measured displacement from ALOS interferograms, with the observed damages on the A-136 road, was useful to assess the potential damage that could cause these slow movements. In general, it is demonstrated that even though PSI analysis provides a better performance in terms of landslide mapping, L-band DInSAR analysis provides an added value for landslide hazard assessment through radar remote sensing. For this reason it is necessary to encourage the launch of new satellite missions similar to ALOS PALSAR that could operate with shorter revisiting time periods. 相似文献
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Integrating Geotechnical and Interferometric SAR Measurements for Secondary Compressibility Characterization of Coastal Soils 总被引：1，自引：0，他引：1
Persistent scatterer interferometry (PSI) provides a new perspective to monitor the movements of coastal structures due to long-term consolidation using satellite-borne remote sensors. The method has the advantages of detecting the displacements at a very high spatial (from 1 to a few meters) and temporal (from 10 to 30?days) resolution. Cost-effective monitoring of complex and large (some kilometer long) structures can be done over long time (up to 10?years) intervals and at large scales (tens times tens km2) of investigation. Here, these measurements are integrated with geotechnical, site-specific measurements to characterize in a unique framework the long-term compressibility of coastal soils over large areas. The approach is tested on the 60-km-long coastland of the Venice Lagoon, Italy. An accurate quantification of the movements of coastal infrastructures at the Venice coastland is carried out by PSI using ENVISAT ASAR and TerraSAR-X images acquired from April 2003 to December 2009 and from March 2008 to January 2009, respectively. Several nearshore and offshore structures were constructed over the decades to protect Venice and its coastal environment from sea storms and high tides. Long jetties were built at the lagoon inlets since the end of the 18th century, significantly reinforced between 1994 and 1997, and finally reshaped since 2003 in the framework of the MOSE construction (i.e., the project of mobile barriers for the temporarily closure of the lagoon to the sea). The measured displacements range from a few mm/year for the structures older than 10?years to 50–70?mm/year for those realized a few years ago. The PSI measurements are combined with the outcome of a detailed geomechanical characterization of the lagoon subsoil obtained by a field-scale experiment started at the end of 2002 and monitored to 2008. The use of the stress-strain properties derived from the trial embankment and the actual lithostratigraphy below the coastal structures, which is available from several piezocone profiles and boreholes, allows for the computation of secondary compression (consolidation) rates that match very well the PSI-derived movements. The results provide important information on the potential of using PSI to characterizing geotechnical properties (magnitude and distribution) of coastal deposits, as well as to estimate the expected time-dependent geomechanical response of coastal structures or other large constructions. 相似文献
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Survey and monitoring of landslide displacements by means of L-band satellite SAR interferometry 总被引：2，自引：2，他引：2
Tazio Strozzi Paolo Farina Alessandro Corsini Christian Ambrosi Manfred Thüring Johannes Zilger Andreas Wiesmann Urs Wegmüller Charles Werner 《Landslides》2005,2(3):193-201
This paper illustrates the capabilities of L-band satellite SAR interferometry for the investigation of landslide displacements.
SAR data acquired by the L-band JERS satellite over the Italian and Swiss Alps have been analyzed together with C-band ERS-1/2
SAR data and in situ information. The use of L-band SAR data with a wavelength larger than the usual C-band, generally considered
for ground motion measurements, reduces some of the limitations of differential SAR interferometry, in particular, signal
decorrelation induced by vegetation cover and rapid displacements. The sites of the Alta Val Badia region in South Tyrol (Italy),
Ruinon in Lombardia (Italy), Saas Grund in Valais (Switzerland) and Campo Vallemaggia in Ticino (Switzerland), representing
a comprehensive set of different mass wasting phenomena in various environments, are considered. The landslides in the Alta
Val Badia region are good examples for presenting the improved performance of L-band in comparison to C-band for vegetated
areas, in particular concerning open forest. The landslides of Ruinon, Saas Grund, and Campo Vallemaggia demonstrate the strength
of L-band in observing moderately fast displacements in comparison to C-band. This work, performed with historical SAR data
from a satellite which operated until 1998, demonstrates the capabilities of future planned L-band SAR missions, like ALOS
and TerraSAR-L, for landslide studies. 相似文献
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Strozzi T. Wegmuller U. Keusen H.R. Graf K. Wiesmann A. 《Geoscience and Remote Sensing Letters, IEEE》2006,3(1):15-18
An analysis of the terrain displacement along a funicular in Switzerland was performed by satellite synthetic aperture radar interferometry using ERS-1/2 data. An initial interferometric point target analysis was performed with images acquired before 1999 and excluding all winter acquisitions with snow cover. The line-of-sight profile of the displacement rate along the funicular shows maximum values of about 1.5 cm/year, with negligible displacements near the lower and upper stations. After the spring of 1999, when displacements of several decimeters occurred because of heavy rainfall, the analysis was continued with single interferograms on the previously identified point targets. With a series of interferograms with large baselines the displacement could be analyzed in 1999 and 2000 along parts of the funicular. 相似文献
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J. Klimeš J. Novotný I. Novotná B. Jordán de Urries V. Vilímek A. Emmer T. Strozzi M. Kusák A. Cochachin Rapre F. Hartvich H. Frey 《Landslides》2016,13(6):1461-1477
Studies focusing on moraine deposits which slide into glacial lakes are scarce, even though they can trigger impact waves responsible for generating glacial lake outburst floods. We focused on landslides in lateral moraines as possible triggers. Detailed geomorphological, geophysical, and satellite radar interferometric investigations of the Palcacocha Lake moraine (Cordillera Blanca, Peru) together with laboratory tests on samples from the site provided data for slope stability calculations using GeoSlope software and hydrodynamic impact wave modeling using the Iber code. We identified landslides that could affect Palcacocha Lake and calculated their stability (factor of safety) under specified conditions, including variable water saturation and earthquake effects. Calculations showed that the moraine slopes are close to the threshold value (Fs?=?1) for stability and are especially sensitive to water saturation. The height of impact waves triggered by a landslide in 2003 and the potential wave heights from newly identified, possibly active landslides were calculated, based on landslide volume estimates, detailed lake bathymetry, and basin topography. Results show that potential future landslide-triggered waves could have similar properties to the 2003 impact wave. Evidence gathered in this study suggests that glacial lake outburst floods triggered by landslides from moraines, however, would be probably smaller than floods resulting from other types of slope processes (e.g., ice/rock avalanches) if dam breach is not taken into account. This assumption has to be critically evaluated against site-specific conditions at a given lake and any possible environmental factors, such as climate change or earthquake that may mobilize larger volumes of moraine material. 相似文献
7.
Giuseppe Gambolati Pietro Teatini Massimiliano Ferronato Tazio Strozzi Luigi Tosi Mario Putti 《地学学报》2009,21(6):467-473
A programme of Venice uplift because of seawater injection into a 600–800 m deep brackish aquifer underlying the lagoon has recently been advanced. As the actual spatial variability of the hydro‐geological parameters is to a large extent unknown, a controversial issue concerns the 25–30 cm heave prediction with the possible generation of differential displacements that might jeopardize the integrity of the architectural patrimony. It is shown that significant differential displacements have occurred in Venice in the past and are still presently occurring as evidenced by SAR interferometry. The results of a stochastic analysis addressing the variability of the hydraulic conductivity of the injected formation indicate that even a highly uneven aquifer expansion does not migrate to ground surface because of the smoothing effect exerted by the overburden. The predicted differential displacements are well below the values Venice is experiencing. Any a priori alarmism appears to be unfounded and unjustified. 相似文献
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