THINKING ON DATUM OF REGIONAL GRAVITY FIELD VARIATION
关于区域重力场变化基准的思考

A space-time datum which is a reference frame plays an important role in the study of regional gravity field variations.Because gravity values related with different space-time datum will be different,whether the datum is reasonable or not,it has a crucial influence on the measured results of gravity variation.We study the characters of space-time datum,estimate the advantages and disadvantages of applicability for the space-time datum.We also give the standard for rational space-time datum of regional gravity field,which could play a key role in valuing the results of gravity variation.The obtained results will effectively improve the quality of our previous results on gravity variation and lessen the difference between calculated modeling and real situation.