Abstract:Based on CMONOC mobile gravity data from 2000, zero drift characteristics of 18 LCR-G relative gravimeters are studied. The results show that zero drift rate of gravimeter may sometime shave a significant change, up to 10 μGal/h. Based on different processing methods of zero drift correction, the results of traditional and improved adjustment models are compared. Given the same priori error, the posterior error of the traditional adjustment model is 39 μGal, and its average accuracy of gravity value is 26.5 μGal; however, for the improved adjustment model, its posterior error is 16.5 μGal and the average accuracy of gravity value is 11.2 μGal. The accuracy of the improved model is much higher than that of the traditional adjustment model. The comparison shows that computing the zero drift correction by circuit in the data preprocessing can effectively eliminate the error of significant change of zero drift. The improved model is superior to traditional adjustment model that assumes the zero drift as a constant.