The Study Of Monitoring And Early Warning For Geological Disaster On LiShui And WenZhou City Based On CORS Network

In recent years,geological disasters in Zhejiang Province have been highly frequent,which has seriously threatened people's life and property safety,and quantitative monitoring of geological disasters is one of the hotspots and difficulties in geosciences.This paper takes Wenzhou City,Lishui City,Zhejiang Province as the research area,and combines the observation data of atmosphere,surface water and sea level change,relies on the load deformation theory,and uses the remove-restore method to calculate the impact of load deformation on seven geodetic elements;CORS station network,combined with atmospheric,surface water and sea level changes and other observations,the high-precision continuous monitoring of ground vertical deformation,ground gravity and ground tilt changes,quantitative monitoring of ground stability,the possibility of geological disasters.The early warning numerical model and the early warning capability of the CORS station network for geological disasters were evaluated.The main work and achievements of this paper are as follows:(1)Introduced the solid earth surface environmental load deformation and the earth gravity field theory.The spherical harmonic function model and the load Green's function model are described in detail.Based on the previous research,the equivalent water high load Green's function is used.The theoretical system of surface environmental load deformation calculation is constructed.(2)Based on the Wenzhou and Lishui,CORS station network in Zhejiang,combined with atmospheric,surface and river and lake reservoir water and sea level changes,satelite precision positioning,environmental load deformation and removal recovery techniques and spherical harmonic analysis methods were used to calculate in detail.From January 2015 to December 2017,the vertical deformation field of the ground(change in height of the earth),the change of the geoid,the normal height change of the ground,the change of ground gravity,the change of ground tilt,the deformation field of the surface deformation,and the deformation field of the surface load,spatial resolution The rate is 2 km×2 km and the time resolution is 1 month.The changes of the earth's high-year change law,the annual variation of ground gravity and the variation characteristics of the ground tilt in the south and west directions are summarized.(3)Proposed independent of any other geological environment information,the ground deformation field and gravity field change monitoring data of the CORS station network are completely constructed,and the ground stability change identification criterion which can be used for quantitative calculation is directly constructed.(4)As for reference,mountain geological disasters such as mudslides and collapses,we continuously optimize and improve the correlation between the reduction of ground stabilit y and the possibility of geological disasters,and realize the quantification of geological disaster precursor capture(space-time positioning),which can accurately express The correlation between the reduction of ground stability and the increase in probabilit y,and the numeric a l model of the early warning of geological hazard covering the scope of the entire CORS station network.It can be obtained,the CORS station network in Wenzhou and Lishui area,with the ability to detect geological disaster precursors and early warning of disaster possibility.