摘要: |
从粘土矿物、碳酸盐矿物、孢粉、介形虫等方面,讨论了西藏扎布耶盐湖晚更新世的气候条件.603±2.7kaB.P.、142.2±7.4kaB.P.时期,扎布耶为间或有一定盐度的淡水湖,前期湖水含盐量比后期高.气候寒冷,风化作用不强,物理风化作用为主.高岭石(60.3±2.7kaB.P.)和厌热性介形虫Radix.Bowelli(142.2±7.4kaB.P.)的出现说明,142.2±7.4kaB.P.时期气候偏干冷,气温比现在低;60.3±2.7kaB.P.气候偏湿冷.比较方解石中Mg含量可知,60.3±2.7kaB.P.比142.2±7.4kaB.P.的湖水盐度高. |
关键词: 晚更新世 阶地 矿物 扎布耶盐湖 介形虫 古气候 |
DOI:10.18307/2005.0104 |
分类号: |
基金项目:国家自然科学基金重点项目(49833010)和国家地质调查项目(200313000065)联合资助. |
|
Late Pleistocene Sedimentation and Palaeoclimate in Zabuye Saline Lake, Northwestern Tibetan Plateau |
LI Minghui1,2, ZHENG Mianping1,2
|
1.Institute of Mineral Resources, Chinese Academy of Geological ScienceCAGS, Beijing 100037, P. R. China;2.Research & Development Center of Saline Lake and Epithermal Deposites, CAGS, Beijing 100037, P. R. China
|
Abstract: |
On the basis of clay, carbonate, pollen and ostracode, it presented the Late Pleistocene climate and environment of Zabuye saline lake in Northwestern Tibetan Plateau.In 60.3 ±2.7kaB.P.and 142.2 ±7.4kaB.P., it was a freshwater lake.Weathering was weak and physical weathering dominated.In 60.3 ±2.7kaB.P., the climate was cold and a little wet,as shown by the appearance of kalinite, and the salinity of water was higher than that of 142.2 ±7.4kaB, P.On the contrary, the climate was cold and a little dry in 142.2 ±7.4kaB.P., and there were many whole shells of ostracodes which implies the water was relatively ralni at that time.Iti addition,the Mg contents of caicite showed that the salinity of palaeo-Lake Zahuye during60.3±2.7kaB.P.was higher than in 142,2±7.4kaB, P. |
Key words: Late Pleistoceneterrace mineralsLake Zabuye ostracode palaeoclimate |