SBAS-DlnSAR monitoring of subsidence induced by extracting brine from an underground salt deposit in Tuzla, Bosnia and Herzegovina

¹ Graduate School of Science and Engineering, Yamaguchi University, 2-16-1 Tokiwadai, 755-8611 Ube, Yamaguchi Prefecture, Japan
² Faculty of Architecture, Civil Engineering and Geodesy, University of Banja Luka, Bulevar vojvode Stepe Stepanovića 77/3, 78000 Banja Luka, Bosnia and Herzegovina
³ Faculty of Mining, Geology and Civil Engineering, University of Tuzla, Univerzitetska 2, 75000 Tuzla, Bosnia and Herzegovina
⁴ Municipality of Tuzla, ZAVNOBiH-a 11, 75000 Tuzla, Bosnia and Herzegovina
⁵ Faculty of Civil Engineering, University of Rijeka, Radmile Matejčić 3, 51000 Rijeka, Croatia

^* Corresponding author: sudi_jbc@yahoo.com

Abstract

Tuzla City, Bosnia and Herzegovina, is very famous for salt mining. The intensive extraction of brine from the underground salt deposit caused accumulative subsidence of up to -12 m from 1956 to 2003. It induced serious damage to residences, buildings, and infrastructures. Although the activity of brine extraction was officially stopped in 2007, reports of subsidence are still on-going for some areas of Tuzla City according to a previous study. In the present study, a satellite-based method, i.e., Differential Synthetic Aperture Radar (DInSAR), is applied for the subsidence monitoring of the induced underground brine extraction. Since October 2014, SAR data obtained by the Sentinel-1A and -1B satellites (European Space Agency: ESA) and Small Baseline Subset (SBAS) multi-temporal analyses have been employed to obtain the spatial distribution and the temporal transition of the land subsidence. The accuracy and effectiveness of the SBAS-DInSAR method are assessed and evaluated by using the real-time kinematic GNSS monitoring system. DInSAR detected that the subsidence is still on-going at a velocity of -36.4 mm/year in some areas, especially in an area northeast of the center of the city. This study presents the validity and effectiveness of SBAS-DInSAR as a useful subsidence monitoring tool.