[1]ZHANG Xi,BAI Zhuoli,LIU Xia.Discussion on the Mechanism of Short-term Anomalies for Cross-fault Short-leveling before the 2016 Menyuan MS6.4 Earthquake[J].Journal of Seismological Research,2020,43(04):644-650.
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Journal of Seismological Research[ISSN 1000-0666/CN 53-1062/P] Volume:
43
Number of periods:
2020 04
Page number:
644-650
Column:
Public date:
2020-09-17
- Title:
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Discussion on the Mechanism of Short-term Anomalies for Cross-fault Short-leveling before the 2016 Menyuan MS6.4 Earthquake
- Author(s):
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ZHANG Xi1; BAI Zhuoli1; LIU Xia2
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(1.The Second Monitoring and Application Center,China Earthquake Administration,Xi'an 710054,Shaanxi,China)(2.The First Monitoring and Application Center,China Earthquake Administration,Tianjin 300180,China)
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- Keywords:
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the Menyuan earthquake; cross-fault deformation; short-term precursors; meta stable-meta instable state
- CLC:
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P315.725
- DOI:
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- Abstract:
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In six months before the 2016 Menyuan MS6.4 earthquake,there were quite more anomalies of mobile cross-fault short-leveling sites within 200 km from the epicenter of the Qilianshan Mountain fracture zone,and collaborative group anomalies dominated by normal features were observed in two months before the earthquake.In this paper,based on the analysis of temporal and spatial evolution of cross-fault deformation and the extraction of the grey relativity index,combined with the auxiliary information of fixed-point continuous deformation and small earthquake activities,we discussed the anomaly mechanism.The results show that the short-leveling observation of cross-fault of Qilianshan Mountain fracture zone at least displayed a meta-stable feature in the short-term stage before Menyuan strong earthquake,deviating from the linear stage,which already had reflected the beginning of stress release and fault synergy,and did exist the possibility of reflecting the characteristics of meta-instable state.