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沿太平洋岛缘的沉积环境被用来模拟解释沿大陆边缘的沉积作用。控制这种沉积作用的是岛缘的构造、火山、气候、水文和生物演化诸条件。低海平面的间歇期可导致含一定量浅海化石的浅水沉积物迁入邻近的深海盆地,在太平洋中部,在过去的130百万年期间可辨认出在浅水化石迁入深海时有八个剥蚀周期。在白垩纪太平洋,影响岛缘沉积作用的洋底水流的流速是缓慢的。然而,自晚白垩世马斯特里赫特期以来,这种底流在中等水深部位剥蚀了沉积物。机械剥蚀作用可能是产生多数沉积间断的原因。经迁移的深海化石的现时数量分布情况显示,在过去42百万年至44百万年期间,在太平洋水体的中、深部位发育着强水流。这些概念对了解深海缺氧沉积环境的分布和发展是重要的。
Sedimentary environments along the Pacific Island margin have been used to simulate sedimentation along the continental margin. Controlling this sedimentation is the island’s tectonics, volcanic, climatic, hydrological and biological evolution conditions. Intermittent periods of low sea level can result in the migration of shallow sediments containing a small amount of shallow sea fossils into the adjacent deep-sea basin. In the central Pacific, over the past 1.3 million years, eight denuded cycle. In the Cretaceous Pacific Ocean, the flow rate of the ocean floor water affecting the island deposition is slow. However, since the Late Cretaceous Maastricht period, this underflow has eroded sediments at moderate depths. Mechanical ablation may be responsible for most of the deposition discontinuities. The present quantitative distribution of migrated deep-sea fossils shows that during the past 42 million to 44 million years, a strong current of water has developed in the middle and deep parts of the Pacific Ocean. These concepts are important for understanding the distribution and development of deep-sea anoxic depositional environments.