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A discussion about how the deep moonquakes are triggered by tidal stress
Received date: 2015-04-02
Revised date: 2015-04-08
Online published: 2016-01-15
Most moonquakes recorded are deep moonquakes that occur at depths of 700-1 200 km, and have a period of about 27 days. We use parallel finite element method and a model with million grids to simulate the tidal stress field and displacement field of the moon numerically. The results show that the maximum shear stress varies with depth. If the moon has a liquid core with a radius of about 700 km or if the moon has a smaller core but the materials at the bottom of lunar mantle are partially molten, the depth of the maximum shear stress will coincide with the depth of the deep moonquakes. The proposition that the moon has a core is lack of sound seismological evidence.Our calculation provides another approach and our result inclines to the suggestion that the moon has a liquid core.
Key words： tidal stress; moonquake; parallel computation; finite element method
ZHANG Bei , ZHANG Huai , SHI Yaolin . A discussion about how the deep moonquakes are triggered by tidal stress[J]. Journal of University of Chinese Academy of Sciences, 2016 , 33(1) : 82 -88 . DOI: 10.7523/j.issn.2095-6134.2016.01.013
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