Lithospheric Equilibrium and Anisotropy around the 2021 Yangbi <i>M</i>s 6.4 Earthquake in Yunnan, China

Guangyu Fu; Zhenyu Wang; Jingsong Liu; Yun Wang

doi:10.1007/s12583-022-1607-3

Volume 34 Issue 4

Aug 2023

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Journal of Earth Science > 2023 > 34(4): 1165-1175.

Guangyu Fu, Zhenyu Wang, Jingsong Liu, Yun Wang. Lithospheric Equilibrium and Anisotropy around the 2021 Yangbi Ms 6.4 Earthquake in Yunnan, China. Journal of Earth Science, 2023, 34(4): 1165-1175. doi: 10.1007/s12583-022-1607-3

Citation:

Guangyu Fu, Zhenyu Wang, Jingsong Liu, Yun Wang. Lithospheric Equilibrium and Anisotropy around the 2021 Yangbi Ms 6.4 Earthquake in Yunnan, China. Journal of Earth Science, 2023, 34(4): 1165-1175. doi: 10.1007/s12583-022-1607-3

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Lithospheric Equilibrium and Anisotropy around the 2021 Yangbi Ms 6.4 Earthquake in Yunnan, China

doi: 10.1007/s12583-022-1607-3

1.
Key Laboratory of Intraplate Volcanoes and Earthquakes (China University of Geosciences, Beijing), Ministry of Education, Beijing 100083, China
2.
Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China

More Information

Corresponding author: Yun Wang, wangyun@mail.gyig.ac.cn
Received Date: 08 Nov 2021
Accepted Date: 27 Dec 2022

Available Online: 01 Aug 2023

Issue Publish Date: 30 Aug 2023

Abstract

Abstract

Using the gravity/GNSS data of 318 stations observed in 2020, this paper optimizes the Bouguer and free-air gravity anomalies around the 2021 Yangbi Ms 6.4 Earthquake, inverses the lithospheric density structure of the focal area, and obtains the distribution of isostatic additional force borne by the lithosphere. The results show that the Bouguer gravity anomaly in western Yunnan varies from -120 to -360 mGal. As a whole the anomalies are large in the north and small in the south, and the value in the source area of the 2021 Yangbi Ms 6.4 Earthquake is about -260 mGal. Significant lateral differences indicates that the crust around the great earthquake does not belong to a solid and stable tectonic unit. The lithosphere in the source area is basically in equilibrium, indicating that the occurrence of the great event is not relative to the lithospheric equilibrium, but to the differential movement of the crust in the horizontal direction. In addition, we obtain the teleseismic SKS phases of 51 stations. As a whole, the polarization direction of fast wave in western Yunnan is approximately vertical to the maximum gradient change direction of regional Bouguer gravity anomaly that reflects the change of Moho.
- the 2021 Yangbi Ms 6.4 Earthquake,
- Bouguer gravity anomaly,
- density structure,
- lithospheric equilibrium,
- shear waves,
- shear wave splitting

Conflict of Interest
The authors declare that they have no conflict of interest.

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References(37)

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