Study On The Gravity Anomaly Correction

The research and application of gravity data have played an important role in the research of structure of the earth, land and resources survey and mineral exploration and other fields of national economy developings. Gravimeter measured in the field of gravity after zero drift correction subtract the based gravity will get the gravity difference. But this gravity difference isn’t the true gravity anomaly, it only can be used to solve some geological problems, so we must do some data processing to this gravity anomaly if we want to make the gravity anomaly is definitely caused by the density of the interior of the earth changes.Gravity correction includes four steps: latitude correction, to eliminatting the influence caused by the latitude difference between measuring point and the base point; height correction, to eliminatting the influence caused by the height difference between measuring point and the base point; terrain correction and the middle layer correction, to eliminatting the influence caused by the terrain ups and downs. At present, the stagnation of gravity correction is still in the middle of the last century that on the premise of model and parameters of the simplified data processing stage, although these correction methods can be applied to local exploration, but on the premise that a large number of simplifying assumptions gravity correction method and the fast development of high precision gravity survey, three component measurement and with its initial or gradient data of 4d dynamic monitoring, precision guidance, obvious contrast to the drilling orientation technology. The bottleneck of regional gravity exploration is gravity correction development lags behind, so the development as seismic data processing method of gravity is imperative.This paper is based on the basis of forefathers’ research, from two aspects of theory and model to further summarizing and perfecting the calculation method of the gravity anomaly correction( includes: height correction, latitude correction, terrain correction and the middle layer correction). Then research the height correction, latitude correction, terrain correction and the middle layer correction method respectively based on plane reference and spherical reference and ellipsoid reference. Research different calibration model, different scope of correction for the effect of the correction and accuracy analysis. Finally we hope to improve the height correction, latitude correction, terrain correction and the middle layer correction method through the analysis of program implementation theory data and actual data processing results, in order to play a role in guiding the practical work.