用离散点观测资料解算走滑断层应变积累时的失真现象及其原因

地震 ›› 2017, Vol. 37 ›› Issue (3): 22-27.

用离散点观测资料解算走滑断层应变积累时的失真现象及其原因

苏小宁^{1, 2}, 孟国杰¹, 石小娟³, 赵倩¹

1.中国地震局地震预测重点实验室地震预测研究所, 北京 100036;
2.同济大学测绘与地理信息学院, 上海 200092;
3.成都市勘察测绘研究院, 四川成都 510100

收稿日期:2016-03-02 发布日期:2019-08-09
通讯作者: 孟国杰, 研究员。 E-mail: mgj@cea-ies.ac.cn
作者简介:苏小宁(1986-), 男, 甘肃白银人, 助理研究员, 主要从事地表形变和断层活动特征研究。
基金资助:
中国地震局地震预测研究所基本科研业务专项(20161ESO10203)和国家自然科学基金(41604007)

Artificial Strain Accumulation Calculated from Discrete Observation Data on a Strike-slip Fault

SU Xiao-ning^1,2,MENG Guo-jie¹,SHI Xiao-juan³,ZHAO Qian¹

1.Institute of Earthquake Science, CEA, Beijing 100036, China;
2.College of Surveying and Geo-informatics, Tongji University, Shanghai 200092, China;
3. Chengdu Institute of Survey & Investigation, Chengdu 510100, China

Received:2016-03-02 Published:2019-08-09

摘要/Abstract

摘要： 利用GPS等离散点观测资料解算因走滑断层闭锁所产生的应变积累时, 在断层附近会产生不可忽略的应变失真现象。失真应变的空间分布特征不会随着测站间距的变化而变化, 但其量值随测站间距缩小而减小, 因此减小测站间距(即加密观测)一定程度上能够削弱失真应变现象。解算应变场时隐含着地壳介质连续均匀性的弹性假设, 但实际的地表形变场并不符合这一假设条件, 这是产生应变失真现象的主要原因。

关键词: 应变, 走滑断层, 测站间距, 离散点观测资料

Abstract: Using GPS or other discrete measurements to calculate strain accumulation caused by fault coupling on strike slip fault, artificial strain cannot be ignored in the vicinity of the fault. The distribution pattern of artificial strain will not change with the change of station spacing. The size of atificial strain will decreases with the decrease of distance between the stations. To a certain extent, reducing station spacing will weaken artificial strain. The assumption of the crustal deformation field continuity is implied in strain calculation,whereas the actual strain field is not consistent with the assumption of the homogeneity of the crustal medium, which results in artificial strain.

Key words: Discrete measurements, Strain, Strike slip fault, Station spacing

中图分类号:

P315.7

苏小宁, 孟国杰, 石小娟, 赵倩. 用离散点观测资料解算走滑断层应变积累时的失真现象及其原因[J]. 地震, 2017, 37(3): 22-27.

SU Xiao-ning,MENG Guo-jie,SHI Xiao-juan,ZHAO Qian. Artificial Strain Accumulation Calculated from Discrete Observation Data on a Strike-slip Fault[J]. EARTHQUAKE, 2017, 37(3): 22-27.

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