New Adjustment of China Gravity Basic Net

Using observation data of the CGBN-85 and new data of absolute and relative measurements after that a new adjustment has been made in 1996. The standard stations occupy 94% of gravity range of CGBN-96 instead of 65% having in the CGBN-85. A new adjustment model is used. Absolute observations with different weight for different gravimeters enter observation equations. The relative observations are taken as quasi-absolute observations with unknowns: station gravity value, gravimeter calibration factors, unknown gravity level and linear drift. Periodic error corrections have not been applied. A comparison between the gravity values of CGBN-96 and those of CGBN-85 were made. After new adjustment the values of CGBN become more reliable.