【摘要】 对首都圈地区由不同施测单位用不同仪器或不同方法获得的三组重力测量数据,通过绝对和相对测量的联合平差、相对测量结果的系统差消除,建立起绝对的、统一的重力时变体系;在此基础上分析了非构造因素地壳沉降的影响,并进行了测点位移改正,消除了长波干扰;实现了绝对和相对测量方法优势互补、消除矛盾和环境干扰、扩大信息量、加密时域采样间隔等目的,提高了识别构造活动过程的能力.结果表明,两组相对测量数据之间以及其中的10期观测资料中存在系统误差,研究区东南部的非均匀性局部地壳下沉导致10个点重力值线性上升,本文用回归分析的方法进行了改正.改正后的重力时变图对1995年10月6日古冶5.0级地震有明显而完整的反映.更多还原

【Abstract】 In the area around the capital of China, three groups of repeated gravity measurements have been obtained by different researchers using different instruments or methods. The simultaneous adjustment of the absolute and relative measurements and systematic error correction among the relative measurements have been carried out in the paper. Thus an unified temporal gravity change system with absolute reference has been established. On the basis of this, the crustal subsidence effect on gravity, which belongs to non-tectonic factor, is analyzed and the displacement of gravity station is corrected, so that the long-wave disturbance is eliminated. As the three groups of gravity measurements are complementary to each other the ability of identifying the tectonic activity process is enhanced. The results showed: there exist systematic errors between the two groups of relative measurements and within the data of 10 campaigns; and the uneven local crustal subsidence in the southeast of the studied area results in a linear rise of gravity value at 10 stations. They are corrected by the regression analysis in this paper. The maps of revised temporal gravity change can obviously and integrally reflect the earthquake M_S5.0 in Guye on October 6, 1995.更多还原