首都圈地区地震重力测量数据的统一处理与分析
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.
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.
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.
引文
董鸿闻,顾旦生,李国智,等.2002.中国大陆现金地壳垂直运动研究[M].西安:西安地图出版社,132~137
郭良迁,薄万举,杨国华.2001.中国大陆的垂直形变速率梯度及地震活动[J].地震地质,23(3):347~356
贾民育,郭有光,高荣胜,等.2001.香山绝对点的重力非潮汐变化[J].地壳形变与地震,21(4):52~57
贾民育,卢造勋,马丽,等.1985a.海城地震流动重力资料清理[J].地壳形变与地震,5(3):225~235
贾民育,刘敬宽,吴兵,等.1985b.论唐山地震前重力变化的可靠性[J].地壳形变与地震,5(3):249~257
贾民育,邢灿飞,孙少安.1994.滇西实验场重力资料的最佳解[J].地震学报,16(增刊):100~108
刘少明,高荣胜,贾民育.2002.香山绝对点周围的局部地壳变形及其对重力测量结果的影响[J].大地测量与地球动力学,22(2):97~100
刘少明,贾民育.2001.重力时变的数学逼近[J].地壳形变与地震,21(3):49~54
马丽,李志雄.1994.北京及其周围地区重力重复测量资料的研究[J].地震地磁观测与研究,15(5):10~17
张祖胜,杨国华,薄万举,等.1996.地壳垂直形变速率梯度、断层形变速率变化与强震危险区研究[J].中国地震,12(4):347
周复恭,汪叔夜,黄运成.1992.应用数理统计[M].北京:中央广播电视大学出版社,272~305
JiaMinyu,GuoYouguang,GaoRongsheng,etal.2004.ThenontidalgravitychangeatXiangshanseismostationinBeijing[J].Newton′sBulletinIssue,(2):14~20
TorgeWolfgang.1989.Gravimetry[M].BerlinNewYork:WalterdeGruyter,322~330
郭良迁,薄万举,杨国华.2001.中国大陆的垂直形变速率梯度及地震活动[J].地震地质,23(3):347~356
贾民育,郭有光,高荣胜,等.2001.香山绝对点的重力非潮汐变化[J].地壳形变与地震,21(4):52~57
贾民育,卢造勋,马丽,等.1985a.海城地震流动重力资料清理[J].地壳形变与地震,5(3):225~235
贾民育,刘敬宽,吴兵,等.1985b.论唐山地震前重力变化的可靠性[J].地壳形变与地震,5(3):249~257
贾民育,邢灿飞,孙少安.1994.滇西实验场重力资料的最佳解[J].地震学报,16(增刊):100~108
刘少明,高荣胜,贾民育.2002.香山绝对点周围的局部地壳变形及其对重力测量结果的影响[J].大地测量与地球动力学,22(2):97~100
刘少明,贾民育.2001.重力时变的数学逼近[J].地壳形变与地震,21(3):49~54
马丽,李志雄.1994.北京及其周围地区重力重复测量资料的研究[J].地震地磁观测与研究,15(5):10~17
张祖胜,杨国华,薄万举,等.1996.地壳垂直形变速率梯度、断层形变速率变化与强震危险区研究[J].中国地震,12(4):347
周复恭,汪叔夜,黄运成.1992.应用数理统计[M].北京:中央广播电视大学出版社,272~305
JiaMinyu,GuoYouguang,GaoRongsheng,etal.2004.ThenontidalgravitychangeatXiangshanseismostationinBeijing[J].Newton′sBulletinIssue,(2):14~20
TorgeWolfgang.1989.Gravimetry[M].BerlinNewYork:WalterdeGruyter,322~330
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心