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| Titel |
Long term landslide monitoring with Ground Based SAR |
| VerfasserIn |
Oriol Monserrat, Michele Crosetto, Guido Luzi, Josep Gili, José Moya, Jordi Corominas |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250095253
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| Publikation (Nr.) |
 EGU/EGU2014-10702.pdf |
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| Zusammenfassung |
| In the last decade, Ground-Based (GBSAR) has proven to be a reliable microwave Remote
Sensing technique in several application fields, especially for unstable slopes monitoring.
GBSAR can provide displacement measurements over few squared kilometres areas and with
a very high spatial and temporal resolution.
This work is focused on the use of GBSAR technique for long term landslide
monitoring based on a particular data acquisition configuration, which is called
discontinuous GBSAR (D-GBSAR). In the most commonly used GBSAR configuration, the
radar is left installed in situ, acquiring data periodically, e.g. every few minutes.
Deformations are estimated by processing sets of GBSAR images acquired during
several weeks or months, without moving the system. By contrast, in the D-GBSAR
the radar is installed and dismounted at each measurement campaign, revisiting a
given site periodically. This configuration is useful to monitor slow deformation
phenomena.
In this work, two alternative ways for exploiting the D-GBSAR technique will be
presented: the DInSAR technique and the Amplitude based Technique. The former is based
on the exploitation of the phase component of the acquired SAR images and it allows
providing millimetric precision on the deformation estimates. However, this technique
presents several limitations like the reduction of measurable points with an increase in the
period of observation, the ambiguous nature of the phase measurements, and the
influence of the atmospheric phase component that can make it non applicable in some
cases, specially when working in natural environments. The second approach, that
is based on the use of the amplitude component of GB-SAR images combined
with a image matching technique, will allow the estimation of the displacements
over specific targets avoiding two of the limitations commented above: the phase
unwrapping and atmosphere contribution but reducing the deformation measurement
precision.
Two successful examples of D-GBSAR landslide monitoring will be analysed and
discussed: the first example is based on DInSAR and concerns to an urban landslide located
in Barberà de la Conca (Catalonia, Spain). This village has experienced deformations since
2011 that have caused cracks in the church and several buildings. The results of a one year
and half monitoring will be shown. The second example is based on the amplitude
based approach and concerns to the active landslide of Vallcebre (Eastern Pyrenees,
Spain). For this site, the results of eight campaigns during a period of 19 months
were performed. During this period displacements of up to 80 cm were measured. |
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