Research on Lateral Features of Upper Mantle Medium in Chinese Central Mainland with Earth's Free Oscillation Normal Modes Excited by Moderate Earthquakes
Abstract This paper selects 14 moderate earthquake (6.5<MW<7.5) events near mainland of China occurred during 2004 to 2015. Analyzing records from Enshi, Kunming and Xi’an stations which are equipped with STS-1 broadband seismographs and records from Lijiang and Wuhan stations which are equipped with superconducting gravimeters, we can obtain observed spheroidal modes. According to the focal mechanism solution of seismic events and lateral homogeneous earth model, we calculate the synthetic values of spherical modes of each station. Then we compare discrepancy in the amplitudes and frequencies between observations and synthetic values to analyze lateral features of underground structure of areas covered by Chinese mainland stations. Results show that the observed amplitudes agree well with synthetic modes at 3.0~6.0 mHz, it’s a clear evidence that there is not large scale lateral inhomogeneous structure in the upper mantle below 200~660 km especially in those areas around selected stations in Chinese central mainland.
WANG Jianguo,HU Xiaogang,LIU Lintao. Research on Lateral Features of Upper Mantle Medium in Chinese Central Mainland with Earth's Free Oscillation Normal Modes Excited by Moderate Earthquakes[J]. jgg, 2018, 38(2): 161-166.
WANG Jianguo,HU Xiaogang,LIU Lintao. Research on Lateral Features of Upper Mantle Medium in Chinese Central Mainland with Earth's Free Oscillation Normal Modes Excited by Moderate Earthquakes[J]. jgg, 2018, 38(2): 161-166.
