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如果知道均匀磁化海山的形状和有关磁异常,就能计算出它的磁化强度和方向。在紧靠夏威夷的几个海山,接近加里福尼亚半岛末端的十二个海山和皮翁涅尔海山观察期间的二十八个海山调查中这种技术已经采用。以太平洋海盆得到的全部有用的古地磁成果已用来确定东北太平洋的原始磁极曲线。这种磁极曲线对白垩纪的点最有利。在北纬61°,东经16°的这个点是17个海山的平均磁极位置,它有一个仅8°的α95。该曲线证实以前的成果所指出的从白垩纪以来东北太平洋有30°的向北运动。从靠近日本的海山所取得的古地磁资料表明,从白垩纪开始东北太平洋与西北太平洋並不经常是刚性接触。南太平洋中长线形断裂带的类型可以用来鉴定太平洋板块上白垩纪以来相对于南极板块的运动,古地磁资料表明,南极板块在同一时间内其纬度保持固定。从东北太平洋和南极所取得的古地磁资料的比较表明,产生了相对运动,这与南太平洋断裂带所表明的相矛盾。如果太平洋的这两个区域在白垩纪至现在之间某一时间内曾经是分离的。则这种矛盾能解决。因此,现在的太平洋板块至少可能是三个不同的板块复合而成,太平洋中的火山无震海脊也许是这些板块的古面边界,而现在已合并成一个单一的板块。
If you know the shape and magnetic anomaly of a uniformly magnetized seamount, you can calculate its magnetization and direction. This technique has been used in 28 sea seam surveys during the observation of a few seamounts in Hawaii and 12 seamounts and Pigeoner seamounts near the end of the California peninsula. All of the useful paleomagnetic results obtained in the Pacific Basin have been used to determine the original polar curves of the northeastern Pacific. This pole curve is most favorable to the Cretaceous. At 61 ° north latitude and 16 ° east longitude, the average magnetic pole position of 17 seamounts has an α95 of only 8 °. This curve confirms that the previous results indicated a 30 ° northward movement of the northeastern Pacific since the Cretaceous. Palaeomagnetic data obtained from seamounts close to Japan indicate that the northeastern Pacific and the northwestern Pacific are not often rigidly in contact since the Cretaceous. The type of mid-long fault zone in the South Pacific can be used to identify the movement of the Pacific plate relative to the Antarctic plate since the Cretaceous. Palaeomagnetic data show that the plate of Antarctica remains constant at the same time. Comparisons of paleomagnetic data obtained from the northeast Pacific and Antarctica have shown that relative motion has occurred, contradicting what the South Pacific fault indicates. If the two Pacific regions were once separated from one another in the Cretaceous to the present. This contradiction can be solved. As a result, the current Pacific plate is, at least, possibly a composite of three different plates. The volcanic, seabed ridges in the Pacific may be the ancient boundaries of these plates and have now been merged into a single plate.