[1]CAI Susu,CHEN Bin.Lithospheric Magnetic Field Distribution in Changning Area,Sichuan Province[J].Journal of Seismological Research,2021,44(04):635-641.
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Journal of Seismological Research[ISSN 1000-0666/CN 53-1062/P] Volume:
44
Number of periods:
2021 04
Page number:
635-641
Column:
Public date:
2021-11-10
- Title:
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Lithospheric Magnetic Field Distribution in Changning Area,Sichuan Province
- Author(s):
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CAI Susu; CHEN Bin
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(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China)
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- Keywords:
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Changning area; lithospheric magnetic field; surface spline; embedded body
- CLC:
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P318.2
- DOI:
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- Abstract:
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The existing geomagnetic field models cannot provide the fine structure of local lithospheric magnetic field in Changning area,Sichuan province. Relied on geomagnetic total intensity measuremed data on 952 stations with 2 km average interval in this area, through data processing such as diurnal variation correction, main magnetic field stripping and surface spline interpolation, we obtained distribution of lithospheric magnetic field in the area near the Changning anticline.The total intensity of the lithospheric magnetic field ranged from -400 nT to 200 nT, with a median of about -4.4 nT, and 90% of the data lies between(-4.4±32)nT. The inner part of the Changning anticline corresponds to a positive region of lithospheric magnetic field, while the anticline boundary corresponds to a negative region. The most significant negative area in the boundary region is located in the northwest end of the Changning anticline, the northeast of the anticline is dominated by positive region, and the south of the anticline is dominated by negative region. The high seismic activity region between the Luochang syncline and the Jianwu syncline corresponds to a positive region of lithospheric magnetic field. The spatial distribution of the lithospheric magnetic field indicates that there are local negative intercalations of the lithospheric magnetic field between the east and west parts of the Changning anticline, which may block the seismic activity of the two parts of the anticline. At the same time, the lithospheric magnetic field gradient in the east and west of anticline presents a differential distribution of high in the west and low in the east.