Detection of the Geodynamics of Earth's Liquid Core by Using Gravity and VLBI Techniques

SUN Heping; LIU Qingchao; CUI Xiaoming; XU Jianqiao

doi:10.13203/j.whugis20180110

Volume 43 Issue 12

Dec. 2018

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Geomatics and Information Science of Wuhan University > 2018 > 43(12): 2058-2063. > DOI: 10.13203/j.whugis20180110

SUN Heping, LIU Qingchao, CUI Xiaoming, XU Jianqiao. Detection of the Geodynamics of Earth's Liquid Core by Using Gravity and VLBI Techniques[J]. Geomatics and Information Science of Wuhan University, 2018, 43(12): 2058-2063. DOI: 10.13203/j.whugis20180110

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Detection of the Geodynamics of Earth's Liquid Core by Using Gravity and VLBI Techniques

1.
State Key Laboratory of Geodesy and Earth's Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China
2.
University of Chinese Academy of Sciences, Beijing 100049, China

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The National Natural Science Foundation of China 41621091

The National Natural Science Foundation of China 41674083

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Author Bio:
SUN Heping, PhD, professor, majors in gravity theory, data processing and applications in geodynamics. E-mail: heping@asch.whigg.ac.cn
Received Date: July 15, 2018
Published Date: December 04, 2018

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Abstract

Abstract

Based on the latest high-precision gravity data recorded in Wuhan and global high-accuracy VLBI (very long baseline interferometry) observations, we have determined the intrinsic parameters (including eigen-period and quality factor, et al) of FCN(free core nutation) of Earth's liquid core. Moreover, the viscosity at the top of the liquid core and its real dynamic ellipticity are obtained. By using the Monte Carlo method, we have calculated the uncertainty of the FCN's eigen-period. The results show that the FCN's eigen-periods determined by gravity and VLBI are about 430 sd and the difference between them is 1.47 sd, with the viscosity coefficient of 1 028 Pa·s. This paper discusses the main reasons for the above differences, and finally compares our results with similar research results from China and abroad.
- gravity,
- VLBI,
- free core nutation parameters,
- physics parameters at core-mantle boundary

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References

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Detection of the Geodynamics of Earth's Liquid Core by Using Gravity and VLBI Techniques

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