Sudy on the pattern of land subsidence change in Tianjin monitored by GNSS
The observation data of 17 GNSS continuously operating stations in Tianjin are processed by using high-precision GNSS solution software to reveal the pattern of land subsidence change,based on datum of GNSS continuously operating station on the bedrock.In order to improve the precision of monitoring land subsidence,some vertical optimal models,optimum parameter settings and adjustment for small scale regional network are used to obtain the long-term GNSS height series.Firstly,the distribution characteristics of cumulative land subsidence in Tianjin,which in the north and east is smaller than that in the west and north,are found.Secondly,the height series show that the trend of land subsidence is slowing down in recent years,but the starting time of slowing down is different in separate height series.Thirdly,the height series reveal the short-term pattern of land subsidence change in Tianjin,including periodic fluctuating and slowly varying subsidence,and the periodic fluctuating subsidence is consistent with the collected data of groundwater depth.Our research can not only provide reference for the prevention and control of land subsidence but also contribute to the next step of hydrogeological analysis.
global navigation satellite system(GNSS)land subsidencegroundwatercontinuously operating stationheight series
万方数据
维普
