 |
| Titel |
Modeling of fast ground subsidence observed in southern Saskatchewan (Canada) during 2008–2011 |
| VerfasserIn |
S. V. Samsonov, P. J. González, K. F. Tiampo, N. d'Oreye |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1561-8633
|
| Digitales Dokument |
URL |
| Erschienen |
In: Natural Hazards and Earth System Sciences ; 14, no. 2 ; Nr. 14, no. 2 (2014-02-14), S.247-257 |
| Datensatznummer |
250118273
|
| Publikation (Nr.) |
 copernicus.org/nhess-14-247-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| Fast ground subsidence in southern Saskatchewan (Canada) between the city of
Saskatoon and Rice Lake was observed with the RADARSAT-2 interferometric
synthetic aperture radar (InSAR) during 2008–2011. We collected 23 ascending
Multi-Look Fine 3 Far (MF3F) and 15 descending Standard 3 (S3) RADARSAT-2
images and performed time-series analysis utilizing Small Baseline Subset
(SBAS) and Multidimensional SBAS (MSBAS) methodologies. We observed two
well-defined circular regions located a few kilometers apart and subsiding
with the nearly constant rate of about 10 cm yr-1. MSBAS
decomposition revealed the presence of both vertical and horizontal ground
displacements. For further analysis we selected two highly coherent
interferograms spanning from November to December 2009 until April 2010
thanks to particularly favorable ground conditions that displayed superior
coherence. We performed modeling and inversion assuming spherical and sill
source models in order to determine the source location, depth and strength.
The sill source model produced the smallest residual of
0.7 cm yr-1 applied to ascending interferograms and
0.9 cm yr-1 applied to descending interferograms. A residual of
1.0 cm yr-1 was achieved with the sill model when both ascending
and descending interferograms were used. This model suggested sources located
at 1.3 and 1.2 km depth with radius of 1.0 and 1.3 km for eastern and
western areas, respectively. The spherical model suggested slightly shallower
sources located at 0.9 and 0.8 km. We could not precisely identify
the cause of this deformation, but the observed subsidence rate and source
depth suggest mining-related origin. Topographic changes produced by this
subsidence rate over a long time may produce shallow groundwater
redistribution and flooding of agricultural lands. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|