3D Density Inversion Of Gravity And Visualization Research

Gravity prospecting in solving the problem of density differences of geology has certain advantages,however,gravity anomaly is from different depth,and different field geology body.Therefore,the conventional gravity data is difficult to obtain 3D geological structure and structural characteristics.Density is an important characteristic of the physical parameters,and the density of the gravity field source body is closely related to the gravitational field,in order to be able to obtain the 3D geological distribution characteristics,more detailed to achieve the purpose of solving geological problems,researching on 3D density inversion and visualization method has important theory value and broad application prospects.But using the computer for 3D gravity data is far more complicated than the 2D inversion study,such as the forward calculation speed,the rationality of the inversion algorithm,the practicability of geological model and so on are all need to study and key issues to be resolved.Is this key problems as the starting point,this paper uses fast algorithm of forward modeling,to research the 3D gravity anomaly forward,adopting least square method to carry out the 3D density inversion of gravity basic research.Based on the MATLAB platform for the research of the 3D geological model of data visualization.In this paper,specific research content mainly includes the following three parts:1)In the study of 3D geological data visualization,according to density is a important physical parameters,developed the 3D geologic body data visualization module.Using 3D grid function,the 3D numerical data smooth function to construct 3D geological data.And the application of 3D data visualization functions,the 3D contour function,3D rotation function,image processing function and the handle control function,realizes the 3D geological body density level and density slice in full space.2)In the study of 3D gravity forward,using the 3D grid technology to establish the cuboid model,use the limited grid nodes instead of the continuous solution space.Derived the gravity anomaly of forward fast algorithm,to solve the problem of forward calculation speed.Applicate forward theory of cuboid geological model,create 3D gravity anomaly forward calculation program.Based on the cube geological model for 3D gravity field characteristic analysis,it is concluded that the geologic body top interface more depth,the gravity anomaly value more smaller;Geological body length increases,the greater the amplitude of anomaly field;Depth of the geological body decurrent parameters is insensitive in the inversion;Geological body width parameter is the most sensitive of 3D several parameters inversion parameters.3)In the study of 3D density inversion of gravity field,in full consideration the size of the model parameters and the forward calculation speed,using the least squares algorithm to achieve the 3D density inversion of gravitational field.Based on the optimal selection method of thinking,create a rectangle element model of 3D gravity anomaly inversion calculation program.With cube geological model,the cuboid geological model and complex geological model,carry out the study of 3D inversion of gravity.