| 摘 要： | This paper deals with the work for obtaining the gravitational value G on the basis of gravitational observation for 5 years at Kunming Observatory using the Birchaiv method in which the zero drift is removed and the theoretical value of earth tides corrected.The gravitational daily mean value G obtained after corrections of zero drift and theoretical values of earth tides shows obvious variations with periods of 15 days and one month respectively and the maximum amplitude of variation reaches approximately to 8μgal.The obtained gravitational monthly mean value Gmonth,also after corrections of zero drift and theoretical value of earth tide shows variation with periods of 6 months and one year respectively.This value tends to be greater in spring and fall and smaller in winter and summer,the maximum variation amplitude of which is about 4 μgal.No clear mutations in the gravitational field in Kunming area have been detected.It is therefore believed that the gravitational field of Kunming area is compara
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