Approximation Of The Gravity Gradient Tensor Based On Trrain And Gravity Data

In this paper,the related theories and methods of perturbation gravitational gradient tensor approximation are studied.The method is used as the main body to study the application of terrain data,gravity data and comprehensive utilization of terrain and gravity data to approximate the perturbation gravitational gradient tensor,and analyze the applicable environment of different methods and advantages and disadvantages.The main work and innovation of this paper are summarized as follows:1.This paper introduces the research background of gravitational gradient,introduces the research status of gravitational gradient measurement at home and abroad,and studies the present situation of gravity gradient tensor approximation.The basic theory of gravitational gradient tensor and perturbation gravitational tensor tensor is introduced in detail.2.In this paper,the prism method,the direct integration method and Gaussler 's method of integration are introduced by using the terrain data to approximate the perturbation gravitational gradient.The relevant experiment is carried out with the measured terrain data and the terrain data range,datum plane and terrain data resolution The influence of the calculation point height on the gradient gravitational tensor is analyzed.The three modeling algorithms are analyzed and compared,and the corresponding applicable conditions are given.3.In this paper,the theory and method of calculating the gravity gradient tensor based on the bit coefficient model are studied.The formulas for calculating the gravity anomaly and the gradient gravitational tensor are deduced in detail.Based on the bit coefficient model,the radial component and perturbation Gravitational vertical gradient truncation error and spectral characteristics;4.Based on the measured terrain data,the corresponding perturbation gravitational gradient tensor is calculated by the bit coefficient model method,and the accuracy of the model is verified.The eigen-6c4 bit coefficient model of the 2191 order is used to solve the disturbance gravitational gradient Tensor full tensor,and prepared a perturbed gravitational gradient full tensor.5.The theory and method of Stokes integral are introduced,and the formulas of Stokes integral and Stokes integral approximation perturbation gravitational gradient tensor are deduced in detail.The removal and recovery techniques are introduced,and the calculation formula and implementation flow are given.Based on the regular prism,the gravity anomaly data and the perturbation gravitational gradient data are simulated.The perturbation gravitational gradient of the points on a line is calculated by plane Stokes integral,and the validity of the method is verified by comparison with the real gradient value.6.The gradient of the gravitational tensor is calculated by Stokes integral,and the gradient tensor is plotted by the gravity anomaly data removed from the measured gravity anomaly data.The gradient gravity tensor is removed from the measured gravity anomaly data Terrain and model,the perturbation gravitational gradient of thecorresponding survey line is solved by Stokes integral,and the discussion and analysis are carried out.7.The basic principle of Bjerhammar theory is introduced,and the theoretical method of approximating perturbation gravitational gradient tensor based on point mass model is introduced.The detailed calculation formula is deduced.The construction process of point quality model is introduced,and the appropriate point mass Depth,the corresponding point mass model is constructed with the measured terrain and gravity anomaly data.The corresponding perturbation gravitational gradient tensor is calculated by using the point mass model,and the results are compared with those calculated by using the high order bit coefficient model.