PSInSAR and DInSAR methodology comparison and their applicability in the field of surface deformations–A case of NW Slovenia

Krištof Oštir,Marko Komac

doi:10.5474/geologija.2007.007

Abstract

In the recent years radar interferometry (InSAR) has become an important tool in various studies. It can be used to produce accurate digital elevation models and observe small surface displacements. Differential interferometry (DInSAR) can detect movements in the radar look direction that are in the order of wavelength used, i.e. less than one centimetre with ERS data. In the presented study DInSAR has been used to observe surface movements in western Slovenia. Three ERS radar images have been supplemented with an external digital elevation model to produce three differential interferograms that temporally covered the Posočje earthquake, which happened on April 12, 1998. For the area around Bovec a land subsidence of approximately 0.5 cm has been observed; the largest movements detected exceeded 2 cm. DInSAR has been compared to the permanent scatterers interferometry (PSInSAR). Both methods are complementary and both have individual advantages and disadvantages.

Highlights

Radar interferometry (InSAR) is a relatively new technique based on stereo pairs of aerial or satellite imagery high resolution images of the Earth's surface
DInSAR has been compared to the permanent scatterers interferometry (PSInSAR)
The DInSAR technology was used in the area of western Slovenia to observe coseismic movements at the Poso~je earthquake event

Summary

Introduction

Radar interferometry (InSAR) is a relatively new technique based on stereo pairs of aerial or satellite imagery high resolution images of the Earth's surface. Its primary fields of application are the production of digital elevation models and detection of minor displacements or deformations in vertical direction. The latter is especially useful in areas where the deformations are hard to measure with classic methods (i.e. geodetic measurements). A special InSAR method, the differential interferometry, is a very useful method that can be applied in ground deformation detection and measurements in the range of the radar wavelength. For ERS satellites the radar wavelength is 5.6 cm resulting in displacement accuracy of approximately half a centimetre (O { t i r, 2000, 2006)

Objectives

Methods

Results

Conclusion