Study On Source-Parameters Estimation Method Base On Analytic Signal Of Full Gravity Gradient Tensor

Gravity exploration is a commonly used geophysical method for geological surveys.It has the advantages of wide measurement range,large detection depth,and good application effect.Compared with gravity anomalies,gravity gradient tensor can better identify weak density anomalies,have higher resolution ability for shallow geological structures,and can provide more abundant field source anomaly information.This paper starting from the gravity anomaly formulas of typical geological bodies and gives the expressions of the full components of the gravity gradient tensor of different geological bodies,Based on this,the concept of a full tensor analytical signal is proposed.This method is suitable for the universal expression of gravity in different geological bodies.Through the derivation of the gravity gradient,we gives the total gradient of the full tensor analytic signal,and we present a method for fast estimation of field source parameters based on the ratio of the total gradient of the full tensor analytic signal and the full tensor analytic signal at different heights.The model tests on 9 single geological bodies including horizontal cylinders,vertical rock veins,horizontal thin plates,vertical steps,spheres,vertical material lines,finite length vertical rock veins,limited width horizontal thin plates,and ultra-large cuboids confirm the method of the paper.Correctness;2D and 3D superimposed model tests are also performed to illustrate the inversion effect of the paper method when superimposed fields.In addition,the noise test results show that by selecting gravity at a certain height for inversion estimation,a more stable and reliable calculation result will be obtained.In the application of the gravity profile on the mines in the Linglong Gob of Shandong Province,the inversion results of the without upward continuation and upward continuation of 100 m are basically the same,indicating that the depth of the two mine centers is about 300 m,both holes can be seen as the shape of a horizontal cylinder.