[1]LIU Lei,ZHU Liangyu,JI Lingyun,et al.Study on the Locking Degree of the Qilian-Haiyuan Fault Zone before the 2022 Menyuan MS6.9 Earthquake and Its Seismic Risk[J].Journal of Seismological Research,2023,46(01):88-98.[doi:10.20015/j.cnki.ISSN1000-0666.2023.0001
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Journal of Seismological Research[ISSN 1000-0666/CN 53-1062/P] Volume:
46
Number of periods:
2023 01
Page number:
88-98
Column:
地震地下流体监测预报理论及技术应用专栏
Public date:
2023-01-01
- Title:
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Study on the Locking Degree of the Qilian-Haiyuan Fault Zone before the 2022 Menyuan MS6.9 Earthquake and Its Seismic Risk
- Author(s):
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LIU Lei; ZHU Liangyu; JI Lingyun; ZHUANG Wenquan; LIU Chuanjin
-
(The Second Crust Monitoring and Application Center,China Earthquake Administration,Xi'an 710054,Shaanxi,China)
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- Keywords:
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the Qilian-Haiyuan Fault Zone; the Menyuan MS6.9 Earthquake; fault locking; seismic risk; crustal deformation
- CLC:
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P315.2
- DOI:
-
10.20015/j.cnki.ISSN1000-0666.2023.0001
- Abstract:
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By using GPS velocity during 2015-2021 and the negative dislocation program,we inverted the locking degree and the slip rate deficit of the Qilian-Haiyuan Fault Zone.Referring to the distribution of small earthquakes in the Fault Zone,we studied the seismic anomalies before the 2022 Menyuan MS6.9 Earthquake,and analyzed the seismic risk of each segment of the Fault Zone.The regional crustal deformation was discussed according to the fault slip rate obtained by the across-fault GPS profile.The results showed that before the Menyuan Earthquake,the seismogenic fault,the Lenglongling Fault,was firmly locked; the locking depth was 15 km,and the slip rate deficit was large,and there were a few small earthquakes.These characteristics were closely related to the medium- and strong-earthquake like the Menyuan Earthquake.The Jinqianghe Fault,the Lenglongling Fault and the eastern segment of the Tuolaishan Fault had deep locking depth,high locking degree,high slip rate deficits,and high seismic risk.Referring to the small-earthquake activity and the locking characteristics of the Lenglongling Fault before the Menyuan Earthquake,we conclude that the medium- and strong-earthquakemay occur in the eastern segment of the Tuolaishan Fault in future.In addition,the strike- slip rate of the Qilian-Haiyuan Fault Zone is between 3.9-4.3 mm/a,and the overall movement of the Fault is consistent.The compression rate(2.9 mm/a)in the western segment gradually decreased to 1 mm/a in the eastern segment.Therefore,the present crustal deformation in the northeastern margin of the Tibetan Plateau is mainly illustrated by the shortening of the Crust in the Mt.Qilianshan area and by the left-lateral,strike-slip of the Qilian-Haiyuan Fault Zone.