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Synthetic Aperture Radar Interferometry
- PROCEEDINGS OF THE IEEE
, 2000
"... Synthetic aperture radar interferometry is an imaging technique for measuring the topography of a surface, its changes over time, and other changes in the detailed characteristics of the surface. By exploiting the phase of the coherent radar signal, interferometry has transformed radar remote sensin ..."
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Cited by 251 (9 self)
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Synthetic aperture radar interferometry is an imaging technique for measuring the topography of a surface, its changes over time, and other changes in the detailed characteristics of the surface. By exploiting the phase of the coherent radar signal, interferometry has transformed radar remote sensing from a largely interpretive science to a quantitative tool, with applications in cartography, geodesy, land cover characterization, and natural hazards. This paper reviews the techniques of interferometry, systems and limitations, and applications in a rapidly growing area of science and engineering.
Synthetic aperture radar interferometry coherence analysis over Katmai volcano group
- Alaska, J. Geophys. Res
, 1998
"... Abstract. ERS-1/ERS-2 synthetic aperture radar interferometry was used to study the 1997 eruption of Okmok volcano in Alaska. First, we derived an accurate digital elevation model (DEM) using a tandem ERS-1/ERS-2 image pair and the preexisting DEM. Second, by studying changes in interferometric oher ..."
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Cited by 47 (20 self)
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Abstract. ERS-1/ERS-2 synthetic aperture radar interferometry was used to study the 1997 eruption of Okmok volcano in Alaska. First, we derived an accurate digital elevation model (DEM) using a tandem ERS-1/ERS-2 image pair and the preexisting DEM. Second, by studying changes in interferometric oherence we found that the newly erupted lava lost radar coherence for 5-17 months after the eruption. This suggests changes in the surface backscattering characteristics and was probably related to cooling and compaction processes. Third, the atmospheric delay anomalies in the deformation interferograms were quantitatively assessed. Atmospheric delay anomalies in some of the interferograms were significant and consistently smaller than one to two fringes in magnitude. For this reason, repeat observations are important o confidently interpret small geophysical signals related to volcanic activities. Finally, using two-pass differential interferometry, we analyzed the preeruptive inflation, coeruptive deflation, and posteruptive inflation and confirmed the observations using independent image pairs. We observed more than 140 cm of subsidence associated with the 1997 eruption. This subsidence occurred between 16 months before the eruption and 5 months after the eruption, was preceded by-•18 cm of uplift between 1992 and 1995 centered in the same location, and was followed by •10 cm of uplift between September 1997 and 1998. The best fitting model suggests the magma reservoir esided at 2.7 km depth beneath the center of the caldera, which was-5 km from the eruptive vent. We estimated the volume of the erupted material to be 0.055 km 3 and the average thickness of the erupted lava to be---7.4 m. 1.
Interferometric synthetic aperture radar (InSAR): its past, present and future
"... Interferometric synthetic aperture radar (InSAR) imaging is a recently developed geodetic technique capable of measuring ground-surface deformation with centimeter to subcentimeter vertical precision and spatial resolution of tens-of-meters over a relatively large region (~10 4 km 2). This paper sum ..."
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Cited by 29 (11 self)
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Interferometric synthetic aperture radar (InSAR) imaging is a recently developed geodetic technique capable of measuring ground-surface deformation with centimeter to subcentimeter vertical precision and spatial resolution of tens-of-meters over a relatively large region (~10 4 km 2). This paper summarizes our recent InSAR studies of several Alaska volcanoes including New Trident, Okmok, Akutan, Kiska, Augustine, Westdahl, Peulik, Shishaldin, and Seguam. The spatial distribution of surface deformation data, derived from InSAR images, enables the construction of detailed mechanical models to enhance the study of magmatic and tectonic processes. These studies will improve our understanding on how the Aleutian volcanoes work and our capability to predict future eruptions and the associated hazards.
Interferometric synthetic aperture radar– GPS integration: interseismic strain accumulation across the Hunter Mountain fault in the eastern California shear
, 2010
"... Mountain fault in the eastern California shear zone ..."
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Cited by 27 (7 self)
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Mountain fault in the eastern California shear zone
A least squares database approach for SAR interferometric data
- Geoscience and Remote Sensing, IEEE Transactions on
, 2003
"... Abstract—This paper presents a least squares (LS) approach for the retrieval of a temporal deformation sequence from a set of interferometric synthetic aperture radar images. The method uses a database of interferograms spanning different long- and short-term intervals, and by solving all the deform ..."
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Cited by 25 (0 self)
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Abstract—This paper presents a least squares (LS) approach for the retrieval of a temporal deformation sequence from a set of interferometric synthetic aperture radar images. The method uses a database of interferograms spanning different long- and short-term intervals, and by solving all the deformations as a unique LS problem provides a chronologically ordered sequence, i.e., a picture of the development of the deformation pattern in time. The approach is illustrated in detail and discussed with respect to both the results of its application on a case study and to possible alternative methods. Index Terms—Ground displacements, least squares methods, synthetic aperture radar (SAR) interferometry. I.
Persistent Scatterer Interferometry (PSI) technique for landslide characterization and monitoring. Remote Sens
"... Abstract: The measurement of landslide superficial displacement often represents the most effective method for defining its behavior, allowing one to observe the relationship with triggering factors and to assess the effectiveness of the mitigation measures. Persistent Scatterer Interferometry (PSI) ..."
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Cited by 21 (3 self)
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Abstract: The measurement of landslide superficial displacement often represents the most effective method for defining its behavior, allowing one to observe the relationship with triggering factors and to assess the effectiveness of the mitigation measures. Persistent Scatterer Interferometry (PSI) represents a powerful tool to measure landslide displacement, as it offers a synoptic view that can be repeated at different time intervals and at various scales. In many cases, PSI data are integrated with in situ monitoring instrumentation, since the joint use of satellite and ground-based data facilitates the geological interpretation of a landslide and allows a better understanding of landslide geometry and kinematics. In this work, PSI interferometry and conventional ground-based monitoring techniques have been used to characterize and to monitor the Santo Stefano d’Aveto landslide located in the Northern Apennines, Italy. This landslide can be defined as an earth rotational slide. PSI analysis has contributed to a more in-depth investigation of the phenomenon. In particular, PSI measurements have allowed better redefining of the boundaries of the landslide and the state of activity, while the time series analysis has permitted better understanding of the deformation pattern and its relation with the causes of
2000), Deformation and seismicity in the Coso geothermal area, Inyo county, California: Observations and modeling using satellite radar interferometry
- J. Geophys. Res
"... Abstract. Interferometric synthetic aperture radar (InSAR) data collected in the Coso geothermal area, eastern California, during 1993-1999 indicate ground subsidence over a 50 km2 region that approximately coincides with the production area of the Coso geothermal plant. The maximum subsidence rate ..."
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Cited by 20 (2 self)
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Abstract. Interferometric synthetic aperture radar (InSAR) data collected in the Coso geothermal area, eastern California, during 1993-1999 indicate ground subsidence over a 50 km2 region that approximately coincides with the production area of the Coso geothermal plant. The maximum subsidence rate in the peak of the anomaly is 3.5 cm yr−1, and the average volumetric rate of subsidence is of the order of 106 m3 yr−1. The radar interferograms reveal a complex deformation pattern, with at least two irregular subsidence peaks in the northern part of the anomaly and a region of relative uplift on the south. We invert the InSAR displacement data for the positions, geometry, and relative strengths of the deformation sources at depth using a nonlinear least squares minimization algorithm. We use elastic solutions for a prolate uniformly pressurized spheroidal cavity in a semi-innite body as basis functions for our inversions. Source depths inferred from our simulations range from 1 to 3 km, which corresponds to the production depths of the Coso geothermal plant. Underpressures in the geothermal reservoir inferred from the inversion are of the order of 0.1-1 MPa (except a few abnormally high underpressures that are apparently biased toward the small source dimensions). Analysis of the InSAR data covering consecutive time intervals indicates that the depths and/or horizontal extent of the deformation sources may increase with time. This increase presumably reflects increasing volumes of the subsurface reservoir aected by the geothermal exploitation. We show that clusters of microearthquakes associated with the geothermal power operation may result from perturbations in the pore fluid pressure, as well as normal and shear stresses caused by the deflation of the geothermal reservoir. 1.
Multidimensional Waveform Encoding: A New Digital Beamforming Technique for Synthetic Aperture Radar Remote Sensing
"... Abstract—This paper introduces the innovative concept of multidimensional waveform encoding for spaceborne synthetic aperture radar (SAR). The combination of this technique with digital beamforming on receive enables a new generation of SAR systems with improved performance and flexible imaging capa ..."
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Cited by 19 (14 self)
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Abstract—This paper introduces the innovative concept of multidimensional waveform encoding for spaceborne synthetic aperture radar (SAR). The combination of this technique with digital beamforming on receive enables a new generation of SAR systems with improved performance and flexible imaging capabilities. Examples are high-resolution wide-swath radar imaging with compact antennas, enhanced sensitivity for applications like alongtrack interferometry and moving object indication, and the implementation of hybrid SAR imaging modes that are well suited to satisfy hitherto incompatible user requirements. Implementationspecific issues are discussed and performance examples demonstrate the potential of the new technique for different remote sensing applications. Index Terms—Adaptive radar, along-track interferometry (ATI), ambiguity reduction, digital beamforming, displaced phase centre antenna (DPCA), ground moving target indication (GMTI), high-resolution wide-swath SAR imaging, hybrid SAR, MIMO SAR, synthetic aperture radar (SAR), waveform diversity. I.
2004), Transient volcano deformation sources imaged with interferometric synthetic aperture radar: Application to Seguam
"... [1] Thirty interferometric synthetic aperture radar (InSAR) images, spanning various intervals during 1992–2000, document coeruptive and posteruptive deformation of the 1992–1993 eruption on Seguam Island, Alaska. A procedure that combines standard damped least squares inverse methods and collective ..."
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Cited by 16 (5 self)
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[1] Thirty interferometric synthetic aperture radar (InSAR) images, spanning various intervals during 1992–2000, document coeruptive and posteruptive deformation of the 1992–1993 eruption on Seguam Island, Alaska. A procedure that combines standard damped least squares inverse methods and collective surfaces, identifies three dominant amorphous clusters of deformation point sources. Predictions generated from these three point source clusters account for both the spatial and temporal complexity of the deformation patterns of the InSAR data. Regularized time series of source strength attribute a distinctive transient behavior to each of the three source clusters. A model that combines magma influx, thermoelastic relaxation, poroelastic effects, and petrologic data accounts for the transient, interrelated behavior of the source clusters and the observed deformation. Basaltic magma pulses, which flow into a storage chamber residing in the lower crust, drive this deformational system. A portion of a magma pulse is injected into the upper crust and remains in storage during both coeruption and posteruption intervals. This injected magma degasses and the volatile products accumulate in a shallow poroelastic storage chamber. During the eruption, another portion of the magma pulse is
Finding realistic dike models from interferometric synthetic aperture radar data: The February 2000 eruption at Piton de la Fournaise
"... Dike intrusions often cause complex ground displacements that are not sufficiently explained by simple analytical models. We develop a method to find complex and realistic dike geometries and overpressures from interferometric synthetic aperture radar (InSAR) data. This method is based on a combinat ..."
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Cited by 15 (1 self)
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Dike intrusions often cause complex ground displacements that are not sufficiently explained by simple analytical models. We develop a method to find complex and realistic dike geometries and overpressures from interferometric synthetic aperture radar (InSAR) data. This method is based on a combination of a boundary element method with realistic topography and a neighbourhood algorithm inversion. Dike model geometry is roughly a quadrangle with its top reaching the ground. The inversion has two stages: search and appraisal. The appraisal stage involves calculations of model marginal probability density functions using misfit values calculated during the search stage. The misfit function takes into account the variance and correlation of data noise. Synthetic tests show that a model is successfully retrieved within predicted narrow confidence intervals. We apply the method on InSAR data of the February 2000 flank eruption at Piton de la Fournaise and get a trapezoid dike dipping seaward (61.0 ◦ – 67.3 ◦ ) with its bottom passing 800–1000 m beneath the summit. A model with a basal slip plane does not better explain observed asymmetric displacements and thus this asymmetry is solely attributed to the dipping dike. The dike lies above a narrow band of pre-eruption seismicity, suggesting that lateral magma propagation occurred. Neglecting topography results in poor modeling at depth and in overestimations of overpressure (or opening), height (both about 30%), and volume (about 20%).