3D Reconstruction Of Magnetic Gradient Tensor Data Target Based On 3D Correlation Imaging

Magnetic exploration is one of the earliest and most widely used geophysical exploration methods,it mainly studies the distribution of detected objects based on the measured magnetic anomaly information.In recent years,with the continuous development of magnetic measurement technology,magnetic gradient tensor anomalies have become more and more important because they have more information,higher resolution than the total field anomaly,and are less affected by the background field and oblique magnetization.The magnetic gradient tensor anomaly has gradually become a research hotspot in the field of magnetic exploration technology and is considered as the next breakthrough point of magnetic detection technology.This article takes this as a starting point to study the physical and morphological inversion methods of magnetic gradient tensor data based on the 3D correlation imaging method.The paper firstly introduces the forward theory of magnetic gradient tensor data,and then introduces the 3D correlation imaging method of magnetic gradient tensor data,and studies the inversion effects of this method in three aspects of spatial resolution,noise data,and magnetization parameters.The experimental results of the model show that the magnetic gradient tensor data 3D correlation imaging method has higher spatial resolution than the magnetic anomaly intensity data three-dimensional correlation imaging method,and has better fault tolerance to noise data and magnetization parameter errors.Related imaging results for the magnetic gradient tensor data 3D correlation imaging method have problems of moving down and stretching along the Z axis,and it is proposed to use the interpolation cutting method to improve it,the experimental results show that the interpolation cutting correlation imaging method can effectively improve the downshift and elongation along the Z axis of the related imaging results of the magnetic gradient tensor data 3D correlation imaging method.The 3D correlation imaging method of magnetic gradient tensor data is only the equivalent physical property distribution of underground space,in order to obtain the physical properties of underground space,a conjugate gradient inversion method based on correlation imaging coefficients is proposed in this paper.By comparing the experimental results of the conjugate gradient method,correlation-based inversion methods based on residual anomalies and conjugate gradient inversion methods based on correlation imaging coefficients,the conjugate gradient inversion method based on correlation imaging coefficients has a simpler calculation process and a highly efficient,what's more,its inversion results are closer to the actual spatial distribution of the model than the other two methods.In order to more clearly characterize the three-dimensional shape of the model of underground space,a more accurate model morphology is obtained.In this paper,a method for inversion of target body shape based on correlation imaging method is proposed.The experimental results of the model show that the method can clearly and accurately depict the spatial pattern of the underground model.Finally,using the method proposed in this paper,the measured magnetic data of Beidaihe area are processed,and obtain the better physical and morphological inversion results.