地震活动性与日月引潮力相关性统计分析

基于ISC地震记录,利用天体动力学中二体问题的轨道方程和摄动理论,确定发震时刻太阳在地面的投影点位置,并进一步计算出太阳相对震中的地心天顶距,将地震按天顶距的大小进行统计,得到地震的太阳天顶距地震频度分布。同样的方法,可得地震的月球天顶距地震频度分布。统计发现:地震的太阳天顶距地震频度和月球天顶距地震频度分布表现出一致的规律性,且较大地震和小地震的活动规律不同,较大地震丛集发生在太阳(月球)天顶距0°和180°附近,与地面引潮力的绝对值分布有较好的一致性;而小地震多丛集在太阳(月球)天顶距60°和120°附近。在此基础上,我们对地震的日月天顶距同时进行统计,建立了日月天顶距地震概率密度分布,结果表明,日月投影点及其对蹠点周围,较大地震发生的概率较高。

Statistical Analysis of the Spatial and Temporal Correlation Between Seismicity and Tide-generating Force by the Sun and the Moon

Based on the ISC earthquake catalogue data,according to the orbit equations of two-body-problem and the perturbation theory of celestial mechanics,we could determine the projection pole of the sun,and thus calculate the zenith distance from the sun to the epicenter.After calculating all the earthquakes on their zenith distances,we could get the distribution of the solar zenith distance versus the occurring probability of earthquakes.By the same method we also obtain the distribution of the lunar zenith distance versus the occurring probability of earthquakes.The results indicate that the distribution of the solar zenith distance versus the occurring probability of earthquakes is quite consistent with the lunar case,and the case for small earthquakes is different from the larger earthquakes.The latter is mainly clustered at 0o and 180o of the zenith distance,and consistent with the distribution of the absolute value of the solar(lunar)tide forces,while the former are clustered at 60o and 120o.Furthermore we set up the solar and the lunar zenith distances versus the occurring probability distribution of earthquakes.The occurring probability of earthquakes near the sun-pole and the moon-pole or their opposite points is higher than the average level.