对渤海湾西岸CH114孔岩心全新世沉积硅藻进行了系统研究，发现硅藻17属28种。与沉积岩石学、年代学（AMS 14C）研究相结合，将该孔自下而上划分为6个硅藻组合带，显示研究区全新世以来经历了从陆到海的演化过程：全新世初期为陆相（组合...对渤海湾西岸CH114孔岩心全新世沉积硅藻进行了系统研究，发现硅藻17属28种。与沉积岩石学、年代学（AMS 14C）研究相结合，将该孔自下而上划分为6个硅藻组合带，显示研究区全新世以来经历了从陆到海的演化过程：全新世初期为陆相（组合1带下部）至受海水影响的盐沼低地环境（组合1带上部）；6646~4280 cal BP年间为受风暴强力事件影响的浅海环境（组合2带）；4280年以来为水深不断变浅的浅海环境（组合3-6带）。CH114孔沉积速率的阶段性变化与河流供给有较好的对应关系：3.6~2.6 ka cal BP和0.4ka cal BP以来两个时段相对较高的沉积速率，分别与黄河三角洲超级叶瓣5的形成和海河独立入海相对应。由硅藻记录的海洋影响的波动变化与全新世气候变化对比显示：研究区海洋影响的增强与气候变暖具有一定的正相关性。CH114孔全新世以来陆海环境的演化，总体上是对气候与海面变化的响应。展开更多
A femur fragment with an Early Lutetian (early Middle Eocene) age is the world’s oldest fossil record from a seal, and, is described as Praephoca bendullensis nov. gen. nov. spec. This find pushes back the earliest e...A femur fragment with an Early Lutetian (early Middle Eocene) age is the world’s oldest fossil record from a seal, and, is described as Praephoca bendullensis nov. gen. nov. spec. This find pushes back the earliest evolution of seals into the Paleocene epoch. The femur has plesiomorphic terrestrial mammal characteristics but has a morphology that is already closer to that of Miocene and present day seals. The Eocene seal femur was found at Fürstenau-Dalum in north-west Germany, in a conglomerate rich in shark teeth that was deposited in a coastal delta environment to the north-west of the central European Rhenish Massif mainland, in the southern pre-North Sea Basin. This discovery has led to a revision of the theory that phocids originated along the coastline of the North American continent. Instead they can now be interpreted to have originated in the tropical Eocene climate of central Europe. Although the fossil records of pinnipeds in Europe during the Eocene, Oligocene and Miocene are extremely sparse, they appear to have inhabited the pre- North Sea basin, within the influence of temperate and arctic upwellings. The distribution of abundant teeth from white and megatooth sharks of two different lineages appears to correlate with that of the seals, which the sharks most probably hunted;providing supporting evidence that the phocids were already adapted as shallow marine coastal inhabitants by this time.展开更多
基金funded mainly by the continued projects of the decadal-long State Geological Investigation Programmeled by China Geological Survey (CGS), State 908 Project and many other projects given by the local governments
文摘对渤海湾西岸CH114孔岩心全新世沉积硅藻进行了系统研究，发现硅藻17属28种。与沉积岩石学、年代学（AMS 14C）研究相结合，将该孔自下而上划分为6个硅藻组合带，显示研究区全新世以来经历了从陆到海的演化过程：全新世初期为陆相（组合1带下部）至受海水影响的盐沼低地环境（组合1带上部）；6646~4280 cal BP年间为受风暴强力事件影响的浅海环境（组合2带）；4280年以来为水深不断变浅的浅海环境（组合3-6带）。CH114孔沉积速率的阶段性变化与河流供给有较好的对应关系：3.6~2.6 ka cal BP和0.4ka cal BP以来两个时段相对较高的沉积速率，分别与黄河三角洲超级叶瓣5的形成和海河独立入海相对应。由硅藻记录的海洋影响的波动变化与全新世气候变化对比显示：研究区海洋影响的增强与气候变暖具有一定的正相关性。CH114孔全新世以来陆海环境的演化，总体上是对气候与海面变化的响应。
文摘A femur fragment with an Early Lutetian (early Middle Eocene) age is the world’s oldest fossil record from a seal, and, is described as Praephoca bendullensis nov. gen. nov. spec. This find pushes back the earliest evolution of seals into the Paleocene epoch. The femur has plesiomorphic terrestrial mammal characteristics but has a morphology that is already closer to that of Miocene and present day seals. The Eocene seal femur was found at Fürstenau-Dalum in north-west Germany, in a conglomerate rich in shark teeth that was deposited in a coastal delta environment to the north-west of the central European Rhenish Massif mainland, in the southern pre-North Sea Basin. This discovery has led to a revision of the theory that phocids originated along the coastline of the North American continent. Instead they can now be interpreted to have originated in the tropical Eocene climate of central Europe. Although the fossil records of pinnipeds in Europe during the Eocene, Oligocene and Miocene are extremely sparse, they appear to have inhabited the pre- North Sea basin, within the influence of temperate and arctic upwellings. The distribution of abundant teeth from white and megatooth sharks of two different lineages appears to correlate with that of the seals, which the sharks most probably hunted;providing supporting evidence that the phocids were already adapted as shallow marine coastal inhabitants by this time.
