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布莱克-巴哈马(Blake-Bahama)盆地,深海钻井计划(DSDP)534井位的IPOD最新钻井资料给出了与北美大西洋板块边缘破裂有关的扩张中心的漂移的确定年龄。布莱克-斯潘 (Blake-Spur)地磁异常测定的为具有基本的卡洛夫年龄。这种地磁异常记录了标志着现代北大西洋诞生的洋脊扩张中心的漂移,比以前设想的年龄年轻约20Ma。由此可以得出一种推断: 引起北大西洋开裂的扩张中心漂移现在具有的年龄指出延伸扩张中心的漂移在墨西哥湾要结束了。有人认为这可能是同一个事件。另一种推断是:沿北美边缘的侏罗纪外层的磁静带需有很高的扩张速度,这种相对高的扩张速度与磁静带之间的关联同白垩纪中期的相似,同时也暗示了在上地幔控制的板块扩张速度过程和在外核控制的磁场过程之间的一种联系。海洋扩张速度的快和慢与地磁场的宁静和反转都具有60—100Ma的周期。由地幔最低层的热物质流的周期性喷发而形成的脉动构造理论能够解释这种相关性。这些喷出物带着热量离开核幔边界,后来达到软流圈和岩石圈,引起快速扩张。在侏罗纪,这种扩张的脉动明显地导致了北大西洋的洋脊开裂。由快速扩张引起的其它一些脉动的出现与地球各部分的多数洋脊破裂有关,这意味着扩张是一种全球性的过程。被动边缘的破裂也许就是受脉动构造理论所描述的较基本的全球性过程的控制。
The latest drilling data from the IPOD Well 534 in the Blake-Bahama Basin and Deepwater Drilling Plan (DSDP) well-established age of drift for the center of expansion associated with the North Atlantic rim rupture. The Blake-Spur geomagnetic anomaly is determined to have a basic Karof age. This geomagnetic anomaly records the drift of the ridge expansion center, marking the birth of the modern North Atlantic, about 20 Ma younger than previously envisaged. From this we can conclude that the age at which the dilatancy of the expansion center that caused the North Atlantic crack now indicates that the drift in the center of expansion is about to end in the Gulf of Mexico. Some people think this may be the same event. Another hypothesis is that the Jurassic magnetostratigraphy along the North American edge needs to have a very high rate of expansion, and this relatively high rate of expansion correlates with the magnetostasis similar to the mid-Cretaceous It also implies a link between plate expansion velocity controlled by the upper mantle and the magnetic field process controlled by the outer core. The speed of marine expansion is both fast and slow and the serenity and inversion of geomagnetic field have a period of 60-100Ma. The theory of ripple tectonics formed by periodic eruptions of the lowest-level thermal-matter flow in the mantle can account for this correlation. These jets leave the core-mantle boundary with heat and later reach asthenosphere and lithosphere, causing rapid expansion. In the Jurassic this pulsation of expansion clearly caused the ridges of the North Atlantic to crack. Some of the other pulsations caused by rapid expansion are related to the majority of ridges in various parts of the globe, which means that expansion is a global process. The rupture of passive edges may be controlled by the more basic global processes described by pulsatile tectonics.