论文部分内容阅读
在野外考察基础上选择湖北郧县庹家湾剖面为研究对象。在对磁化率和粒度进行分析的同时,用单片再生剂量法进行了光释光测年(OSL)地层断代。OSL测年数据显示:剖面样品年龄处在55.11~13.57ka BP,且与地层深度呈现出良好的对应关系,此剖面为黄土风化堆积形成。黏粒含量、黏粒/粉砂值以及磁化率值等气候替代性指标数值在马兰黄土层228~260cm和294~370cm深度明显高于典型马兰黄土(L1),具有明显的成壤特征,通过OSL测年数据判断时间为27.26~21.59ka BP,说明在晚更新世时期气候并非持续稳定的寒冷干旱,而是具有一定的波动,在此期间气候相对温暖湿润,而且此次气候事件在黄土高原地区其他沉积记录中也有良好记录。
Based on the field investigation, we selected the Jujiawan section of Yunxian County in Hubei Province as the research object. Optical susceptibility dating (OSL) stratigraphic dating was carried out using monolithic regeneration dose method while analyzing the magnetic susceptibility and particle size. According to the OSL dating data, the age of the profile sample is 55.11 ~ 13.57 ka BP, which shows a good correspondence with the depth of the formation. This profile is formed by loess weathering and accumulation. Clay-content, clay / silt and magnetic susceptibility values were significantly higher than those of the typical Malan loess (Ll) in the Loess-Malan loess at 228 ~ 260cm and 294 ~ 370cm depths, The determination time of OSL dating data is 27.26 ~ 21.59ka BP, which shows that the climate was not stable and cold during the late Pleistocene, but had some fluctuations. During this period, the climate was relatively warm and humid, and the climate event occurred in the Loess Plateau There are also good records of other sedimentary records in the area.