Curved-grid kriging gridding method and its application to near-station terrain correction in gravity measurement
TANG Xiao-Ping1,2, LIU Kuan-Hou1, GENG Tao1, FENG Zhi-Han1
1. Xi'an Center of Geology Survey, China Geology Survey, Xi'an 710054, China;
2. Key laboratory for the Study of Focused Magmatism and Giant ore Deposits, MLR, Xi'an 710074, China
In this paper,a high-accuracy and strong stability near-zone terrain correction method is discussed.Firstly,combining Kriging gridding method with curved-grid computation technology,a Curved-Grid Kriging Gridding Method(short for CGKG-M)and its extending edge techniques are implemented to realize data-gridding in circle area;Next,this method is used to compute near-zone terrain correction value and realize the gravity measurement near-zone terrain correction value's computation which contains any angles and circles.Finally,some modeling tests,real data computation and error analysis of this method are carried out.The research result has shown that CGKG-M near-zone terrain correction value computation method has some characteristics,such as high computation accuracy,strong stability and flexibility.It is a simple,efficient and fast method for near-zone terrain correction value computation which matches the measurement data form of GTCS-1 gravity measurement near-station correction instrument.
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