Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang 050061, China.
Key Laboratory of Quaternary Chronology and Hydrological Environment Evolution, China Geological Survey, Shijiazhuang 050061, China.
Ying Yong Sheng Tai Xue Bao. 2021 Feb;32(2):453-466. doi: 10.13287/j.1001-9332.202102.009.
The Quaternary sediment in the Ningbo Coastal Plain was the deposit due to sea-land interaction, which recorded information of past climate changes. The region is therefore an ideal area to study paleoclimate changes and sedimentary characteristics. We determined the stratigraphic division and paleoenvironmental evolution based on C and paleomagnetic dating, along with detailed analyses of lithology, pollen assemblage, foraminifera and ostracodes assemblage, and grain size of sediment in core Z02 located in the southeastern Ningbo Coastal Plain. The results showed that the boundary between the Holocene and Upper Pleistocene in the core Z02 record was at 30.5 m, the boundary between the Upper and Middle Pleistocene was at 82.65 m, and the boundary between the Quaternary and Lower Cretaceous was at 90 m. The Middle Pleistocene section of the core contained few sediments, while the Lower Pleistocene section was completely missed. During the late Pleistocene, the hydrodynamic conditions experienced energy levels of medium to medium low to medium, and sedimentary facies changed from alluvial lake to overbank to river to lake to alluvial lake to lake to overbank. During the Holocene, the hydrodynamic changes experienced energy levels of medium low to low to medium, and the sedimentary facies changed from shoreland to shallow sea to shoreland lake. The Ningbo Coastal Plain had experienced tectonic uplift, weathering and erosion stage in the Early and Middle Pleistocene, from warm and humid to dry in the Late Pleistocene, and from warm and humid to dry and cool in the Holocene, as revealed by the core Z02 record. This study provided useful information in investigating past environmental changes in the subtropical coastal region of eastern China.
宁波滨海平原的第四纪沉积物是海陆相互作用的产物，记录了过去气候变化的信息。因此，该地区是研究古气候变化和沉积特征的理想区域。我们根据 C 和古地磁测年，以及对岩性、花粉组合、有孔虫和介形虫组合以及核心 Z02 沉积物粒度的详细分析，确定了地层划分和古环境演化。结果表明，Z02 岩芯中全新世和上更新世的边界在 30.5 米处，上更新世和中更新世的边界在 82.65 米处，第四纪和下白垩纪的边界在 90 米处。岩芯中中更新世部分沉积物较少，而下更新世部分完全缺失。晚更新世期间，水动力条件经历了中等到中低到中等的能量水平，沉积相从冲积湖变为漫滩到河流到湖泊到冲积湖到湖泊到漫滩。全新世期间，水动力变化经历了中低到低到中等的能量水平，沉积相从滨岸到浅海到滨岸湖。Z02 岩芯记录表明，宁波滨海平原在早、中更新世经历了构造抬升、风化和侵蚀阶段，晚更新世从温暖湿润到干燥，全新世从温暖湿润到干燥凉爽。本研究为研究中国东南亚热带沿海地区过去的环境变化提供了有用的信息。
