Vertical ground displacements in the Shandong Province derived from long-term GNSS and leveling surveying

Abstract

The vertical movement is comprised of both vertical crustal movements and vertical ground movements. Vertical crustal movement is established by using a cubic polynomial model with first-order leveling data from four separate time periods (1958–2015) in the Shandong Province and neighboring areas, and the vertical motion is formed from continuously operating reference stations (CORS) data (2010–2015) with GAMIT/GLOBK and a linear regression estimation in the Shandong Province. Vertical ground movement can be obtained by subtracting vertical crustal movement from vertical motion. Vertical crustal movement of Shandong Province gradually changes from descending to ascending along the northwest to the southeast, and the rate varies from −5.9 to 6.2 mm/year (mm/yr). Three distinct settlement areas including Guangrao, Dezhou and Heze are analyzed in detail. Substantial subsidence with a maximum rate of 78.2 mm/yr occurred in northern and western areas of Shandong Province. Slight uplift with a maximum rate of 8.4 mm/yr occurred in central region and Jiaozhou Peninsula of Shandong Province. The vertical ground movements are basically consistent with vertical movements in the Shandong Province.