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本文根据各学科的证据,对正在出现的有关早第三纪(65—24百万年前)大洋环流史和气候变化史的观点进行了评论。评论的重点放在白垩纪与第三纪界限(65百万年前),古新世末一早始新世(53—49百万年前)及接近始新世与渐新世界限(38百万年前)的深刻影响过世界大洋的海洋史和气候史的重大事件上。在重建早古新世、中始新世和晚渐新世期间古地理的基础上推断和绘制了全球海面环流图。早第三纪的特征是高纬度温度发生下降监形成较大纬向热差异,它们最终导致了晚第三纪以冰川为主的状态。根据一种模式,在早第三纪期间,深层水形成的方式从晚白垩世所特有的以低、中纬度区边缘海中生成温暖的、成的底层水为主变为现代所特有的以高纬度区产生冷的、高密度的底层水为主。早第三纪浮游生物的生物地理资料(生物组合越过纬度的迁移)及氧同位素资料证明变冷事件发生在中古新世、中始新世及接近始新世与渐新世的界限,而主要的变暖事件则在早始新世达到高峰。生物地理资料还表明在古新世初和渐新世中期发生过一些次一级的变冷事件,在中始新世晚期则发生过一次次一级的变暖事件。浮游生物的迁移资料表明渐新世中期的变冷事件可能与接近始新世与渐新世界限的那次事件一样强烈。
Based on the evidence from various disciplines, this article comments on the emerging views on the history of the ocean circulation and climate change in the early Tertiary Period (65-24 million years ago). The commentary focused on the Cretaceous and Tertiary boundaries (65 million years ago), the late Paleocene-early Eocene (53-49 million years ago), and close to the Eocene and Oligocene boundaries (38 Thousands of years ago) had a profound impact on the major events of the oceans and climate history of the world oceans. Based on the reconstruction of the Paleocene, Middle Eocene and Late Oligocene paleogeography, the global sea surface circulation map was deduced and drawn. The characteristics of the Early Tertiary are the high latitudinal thermal differences resulting from the declining temperature at high latitudes, which ultimately led to the glacial-dominated state in the Late Tertiary. According to one model, during the early Tertiary period, the formation of deep water changed from a warm, subterranean water that originated from the Late Cretaceous margins in the margins of low and mid-latitudes to a modern, Latitude produces cold, high-density bottom water. The biogeographic data of early Tertiary plankton (migration of biological assemblages beyond latitude) and oxygen isotope data show that the chilling events occurred in the Middle Paleocene, middle Eocene and near Eocene and Oligocene boundaries, whereas the main Warming events peaked in the early Eocene. Biogeographic data also indicate that some sub-level chilling events occurred during the beginning of Paleocene and mid-Oligocene, and sub-level warming occurred in the late mid-Eocene. Plankton migration data indicate that the mid-Oligocene chilling event may be as strong as the one close to the Eocene and Oligocene boundaries.