【摘要】 198 8年 3月～ 2 0 0 1年 3月中国地震局和中国计量科学院合作用NIM Ⅱ仪器在香山地震台进行了 5 8次绝对重力测量 ,其中 4 4次同时量测了地下水水位。本文从多角度研究了香山点重力变化的机理。主要结论 :(1)地下水活动是重力变化的主要局部干扰源 ,它与重力观测值分段相关 ,可用一个 5次多项式进行改正 ;(2 )局部地壳形变的影响甚小 ,可略而不计 ;(3)地震活动导致重力值发生短期变化 ,最大幅度达 0 .333μms- 2 ;(4) 1989～ 2 0 0 1年重力值近于线性地下降了 0 .191μms- 2 ,平均速率为 - 0 .0 147μms- 2 /a ,属全球性或区域性重力变化更多还原

【Abstract】 From March, 1988 to March, 2001, 58 times of absolute gravimetries were carried out by China Seismological Bureau cooperating with China Institute of Metrology with the instrument NIM Ⅱ at Xiangshan seismostation, and 44 times of groundwater level measurements were carried out simultaneously. This paper studies the mechanism of gravity change at Xiangshan station from various aspects. The main conclusions are drawn as follows:(1)the groundwater activities are the main local interferential sources which correlate with gravity observation values by segments and can be corrected by a 5 th order polynomial; (2) the effect of local crustal deformation is very small, thus it can be ignored; (3) the earthquake activity will result in short term change of gravity value and its maximum magnitude comes to 0.333?μms -2 ; (4) from 1989 to 2001, the gravity value approximately linearly drops 0.191?μms -2 . The average drop rate is -0.0147?μms -2 /a. This gravity change belongs with global or regional gravity change.\;更多还原