Usefulness of synthetic aperture radar (SAR) interferometry for digital elevation model (DEM) generation and estimation of land surface displacement in Jharia coal field area

Abstract

Land surface displacement is a phenomenon of ground movement, which may occur due to various reasons including unplanned mining. The quantification of land surface displacement through conventional field surveys is based on sparingly distributed point data, which may be insufficient for many applications. A detailed spatial and temporal monitoring of land surface displacements through remote sensing-based synthetic aperture radar (SAR) interferometry may be valuable. Over the last two decades, differential SAR interferometry (DInSAR) has been effectively used globally for the estimation of spatial land surface displacements caused due to natural and man-made hazards. However, it has not gained momentum in India, where occurrences of natural and man-made hazards are a common phenomenon. In this article, preliminary results from DInSAR to measure land surface displacement in Jharia coal fields have been presented. DInSAR results effectively identified the land surface displacement due to several mining activities in the region during a one-month period.

Keywords:

• SAR interferometry (InSAR)
• interferogram flattening
• adaptive filtering
• digital elevation model (DEM)
• differential SAR interferometry (DInSAR)

Acknowledgements

The SAR images have been procured by Eurimage S.p.A Club, Rome, Italy for the research work. The processing has been done on GAMMA_ISP/DIFF_GEO software procured under Department of Science and Technology (DST) funded research scheme. The authors would like to thank the anonymous reviewers for their candid comments and suggestions, which significantly improved the quality of this article.