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海山磁异常反转以及DSDP(深海钻探计划)所获的古地磁和赤道沉积相的资料,都清楚地表明,在晚始新世,太平洋板块存在着一个古地磁极。磁极的位置在77.5°N、21.2°E。这说明在最近的41±5百万午内,太平洋板块的视磁极移动了12.5±1.6°。晚始新世的古磁极与置信度为95％的太平洋马斯特里赫特磁极的位置相差甚远,这表明在距今69百万年到41百万年间,太平洋视磁极移动了7.2°。晚始新世古地磁极的数据采集地散布在北太平洋的广大地区,因此,数据的一致性便支持着这样一种假说:始新世以来,中太平洋北部板块一直是刚性的。晚始新世磁极与根据热点模式预测的太平洋运动的一致性,意味着自那时以来,自转轴与热点间的相对运动已经很小。此外,这一发现还证明,其它作者推得的白垩纪以来所发生的大量热点对自转轴的运动,必定是以更快的速率发生,且是在始新世以前结束的。
Data on the reversal of seamount anomalies and paleomagnetic and equatorial sedimentary facies obtained by the DSDP (Deep Sea Drilling Project) clearly show that there was an ancient paleomagnetic pole in the Pacific Ocean during late Eocene. The pole position is at 77.5 ° N, 21.2 ° E. This shows that in the recent 41 ± 5 million hours, the apparent pole of the Pacific plate moved 12.5 ± 1.6 °. Late Pleistocene paleomagnetic poles are far from the Pacific Maastricht poles with a 95% confidence level, indicating that in the period from 69 million to 41 million years ago, the apparent magnetic poles of the Pacific moved by 7.2 ° . Late Pleistocene paleomagnetic pole data was collected in a wide area of the North Pacific Ocean. Therefore, the consistency of the data supports the hypothesis that since the Eocene, the northern plate of the Central Pacific has always been rigid. The coincidence of Late Pliocene poles with the Pacific motion predicted from the hotspot model means that since then, the relative motion between the spinning axis and the hotspot has been small. In addition, the finding also demonstrates that the mass of hot spots that have occurred since the Cretaceous years by other authors must have occurred at a faster rate than the spin axis and ended before the Eocene.