地球韵律的时空表现及动力问题

文章介绍了大洋底１５６６Ｍａ以来六个时段增生构造的划分，前五个时段平均３０Ｍａ，具一定韵律性，以此与中国大陆１７５Ｍａ以来岩浆 构造活动的分段进行了比较，它们共同的韵律时段是（３０±８）Ｍａ。文中还介绍了一组全球地震活动的分幕性及其空间展布的有趣现象，包括低、中纬度与高纬度地震２０年左右的交替活动，南、北极区地震的交替活动，Ｍｓ≥８级大震呈现正交型与斜交型全球图像的分幕性交替活动，还有地球转速加速期和减速期地震发生地区的韵律性分布等。就上述中期和短期的地球韵律表现，进行了地球韵律判定的复杂性和动力学背景的讨论，强调了地球韵律的应用和地球本体研究的重要性。

TIME-SPACE INDICATIONS OF THE EARTH′S RHYTHM AND ITS DYNAMICS

This paper presents the time division of the seafloor accretion tectonics since 156.6 Ma. Six periods of accretion can be determined among which the former five have the duration of 30 Ma in average and certain rhythm. We compare these with the time division of the magma tectonic activities in China mainland since 175 Ma. It is noticed that they have a common period of rhythm about (30±8) Ma. This paper also presents a group of interesting phenomena on the episodes of global seismicity and its spatial distribution. They include the alternating seismicities of about 20 years on the low, mid and high latitudinal zones, the alternating seismicities on the antarctic and arctic regions, the episodical alternating seismicities of M 8 with orthogonal and oblique intersecting global patterns, as well as the rhythm distribution of seismic regional scales associated with the quickening and decelerating periods of Earth′s rotation. In light of these indications of Earth′s rhythm of mid and short terms, complications of identifying the Earth′s rhythm and its dynamic background are analysed. It is emphasized that studies on the Earth′s rhythm and the Earth itself are of great importance.