汶川地震震后短期青藏高原东北缘地壳变形特征成因讨论

地震 ›› 2013, Vol. 33 ›› Issue (3): 124-132.

汶川地震震后短期青藏高原东北缘地壳变形特征成因讨论

李强¹, 江在森¹, 武艳强¹, 赵静², 魏文薪¹, 刘晓霞¹

1.中国地震局地震预测重点实验室, 北京 100036;
2.中国地震台网中心,北京 100045

收稿日期:2013-01-29 出版日期:2013-07-31 发布日期:2020-09-28
作者简介:李强 ( 1985-),男,辽宁铁岭人,在读硕士研究生,主要从事GPS地球动力学等研究。
基金资助:
国家自然科学基金项目(40974005)

Discussion on the Implications of Short-term Crust Deformation Characteristics in the Northeastern Margin of Tibetan Plateau after the 2008 Wenchuan Earthquake

LI Qiang¹, JIANG Zai-sen¹, WU Yan-qiang¹, ZHAO Jing², WEI Wen-xin¹, LIU Xiao-xia¹

1. Key Laboratory of Earthquake Prediction, Institute of Earthquake Science, CEA, Beijing 100036, China;
2. China Earthquake Networks Center, Beijing 100045, China

Received:2013-01-29 Online:2013-07-31 Published:2020-09-28

摘要/Abstract

摘要： 2007—2009年时段GPS数据资料显示青藏高原东北缘地区地壳运动较前期(1999—2007年时段)发生明显变化。本文分别对汶川地震同震影响、震后粘弹性松弛影响和震后余滑影响进行了分析。结果表明, 同震对该区域地壳变形特征的形成存在一定影响, 而震后粘弹性松弛和余滑产生的影响均可忽略不计。分析认为, 对于中国大陆这种多块体系统而言, 现有的震后变形机制并不能充分解释震后短期某些区域地壳运动变形特征的形成, 汶川地震震后短期青藏高原东北缘的地壳变形特征的形成可能主要与震后块体运动调整有关。

关键词: 震后影响, 块体运动调整, 地壳变形, 青藏高原东北缘

Abstract: Crust movement changed obviously in the northeastern margin of Tibetan Plateau zone according to GPS measurements during 2007—2009. This paper analyzed the coseimic effect and postseismic viscoelastic relaxation and afterslip effect respectively. The results show that some deformation was formed because of coseismic effect, but the postseismic viscoelastic relaxation and afterslip effect can be neglected. Some characteristics of postseismic short-term deformation can not be explained adequately by the deformation mechanics for China mainland, which belongs to multi-block system. To a large extent, the form of the characteristic of postseismic short-term deformation in the northeastern margin of Tibetan Plateau zone may be related to adjustment movement of blocks.

Key words: Short-term Crust Deformation, GPS, Northeastern Margin of Tibetan Plateau, Wenchuan earthquake

中图分类号:

P315.7

李强, 江在森, 武艳强, 赵静, 魏文薪, 刘晓霞. 汶川地震震后短期青藏高原东北缘地壳变形特征成因讨论[J]. 地震, 2013, 33(3): 124-132.

LI Qiang, JIANG Zai-sen, WU Yan-qiang, ZHAO Jing, WEI Wen-xin, LIU Xiao-xia. Discussion on the Implications of Short-term Crust Deformation Characteristics in the Northeastern Margin of Tibetan Plateau after the 2008 Wenchuan Earthquake[J]. EARTHQUAKE, 2013, 33(3): 124-132.

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