青海玉树地震的天文背景分析

Analysis of astronomical background of Yushu earthquake in Qinghai

系统地分析了青海玉树地震发生时的天体位置、太阳活动与地球自转等天文因素的影响.从大的长期天文背景来看,玉树地震发生于中国大震频发的月亮白赤交角由极大变到极小时期,并且是太阳活动的偶数周;从短临看,玉树地震正好发生在地球自转与太阳黑子数发生突跳的时期,且此时震中所受的天体引潮力加速度又处于其变化速率最大的极值附近.研究结果表明,这些天文因素对玉树地震的孕育与发生起到了不可忽视的作用,是值得进一步深入研究的.

This paper analyses systematically the astronomical background when the Yushu earthquake occurred, such as the positions of celestial objects, solar activities and earth rotation, etc. The analysis results show that from view of long period, the Yushu earthquake occurred at the time when major earthquakes in China frequently occur during the inclination between the Moonrs path and Earth% equator changing from its maximum to minimum and in the even cycle of the solar activity; from view of short time, it occurred at the time when sudden variations appeared in both the acceleration of Earth＇s rotation and sunspot numbers, as well as the time near the maximum of the changing rate of the celestial tide generating force acceleration at the epicenter. These all show that for either the pregnancy or the occurrence of the earthquake the influence of these astronomical factors can not be ignored and merits further in-depth research.