滇西北金沙江小中甸盆地晚更新世的介形类及其古环境

Late Pleistocene Ostracods in the Xiaozhongdian Basin,Jinsha River Valley,North—Western Yunnan,and Their Paleoenvironmental Significance

本文研究了滇西北地区金沙江小中甸盆地两条剖面(A和B)的介形类组合特征。据地层沉积特征和介形虫分布规律,结合光释光测年数据和野外调查研究,初步认为滇西北金沙江小中甸盆地存在倒数第二次冰期末期和末次冰期早冰阶的沉积,气候以冷湿为主,间以短暂的温干、冷干变化。

Two profiles （A and B） in the Xiaozhongdian Basin, north--western Yunnan, were investigated for the characteristics of the ostracod assemblage. Based on the sedimentation characteristics and ostracod distribution, combined with OSL （optically stimulated luminescence） dating and field investigation, we got the preliminary conclusion that deposits of the last stade of the penultimate glaciation and the early stade of the last glaciation exist in the Xiaozhongdian Basin, north--western Yunnan. The climate during the two stades was generally cold-wet, with short warm-dry, and cold-dry oscillations.