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白垩纪超静磁带(CNS)是指白垩纪中期约40 Ma内(Aptian Santonian, 121~83 Ma)地球磁场没有出现倒转的异常现象。这一现象引起地球学界的极大关注,原因在于它与白垩纪中期(124~90 Ma)其他一系列事件在时间上非常吻合,包括洋底扩张速率的快速增加和洋底高原、海山链、大型火成岩省等生产速率的快速增加。过去20多年许多研究强调所有这些现象与下地幔对流的联系。近期研究的一个重要的进展在于把地球磁场的变化(反转频率和古强度)与许多重要的地质和地球物理过程结合起来,如周期性地幔对流、地幔柱活动、全球热流、真极移、大型火成岩省的产生和生物群集绝灭。文中回顾了白垩纪地球磁场研究以及与白垩纪中期所发生的全球性的地质事件之间的可能存在的关联,并讨论在这一重要研究领域内未来研究的发展方向。
Cretaceous ultra-quiet magnetic tape (CNS) refers to the anomalous phenomenon that the Earth’s magnetic field does not reverse in about 40 Ma in the mid-Cretaceous (Aptian Santonian, 121-83 Ma). This phenomenon has drawn great attention from the earth science community because it coincides in time with a series of other events in the mid-Cretaceous (124-90 Ma), including the rapid increase of the ocean floor expansion rate and the increase of the ocean bottom plateau, the seamount chain, Igneous province and other production rates increased rapidly. Many studies over the past two decades have emphasized the connection of all these phenomena with the convection of the lower mantle. An important advance in recent research is the combination of changes in the Earth’s magnetic field (inversion frequency and paleo-intensity) with many important geological and geophysical processes such as periodic mantle convection, mantle plume activity, global heat flux, true pole migration, Large igneous province and the emergence of biological clusters extinction. This paper reviews the possible correlation between Cretaceous Earth’s magnetic field studies and the global geological events that occurred in the mid-Cretaceous and discusses the future direction of research in this important area of research.