北京猿人洞穴堆积气候地层的重新划分与对比

CLIMATIC STRATIGRAPHIC RE-DIVISION AND CORRELATION OF CAVE SEDIMENTS AT LOCALITY 1 IN ZHOUKOUDIAN, BEIJING

周口店第一地点洞穴四十余米厚的堆积层自下而上共分为 17层 ,新近测量的年代推前了近 2 0 0 ka。对堆积层所含哺乳动物化石和孢粉资料进行聚类统计和因子分析 ,结合风化系数和微量元素含量等古气候代用指标 ,重新定量地描绘它所记录的古气候波动旋回。根据第 2层 TIMS测年为 410 ka B.P.,第 14层上部是磁性地层测量的B/ M界线 ,可以将该洞穴堆积层 1— 14层对比于深海岩心 δ1 8O气候曲线的 11— 19段或中国黄土—古土壤序列S4— S7,并且古气候旋回内的次级波动也可进行一定程度的对比。

The cave sediments at Locality 1 in Zhoukoudian, Beijing, more than 40m thick, have been divided into 17 layers. According recent dating by TIMS, the age of the sediments has been prolonged by about 200 ka. On the basis of cluster and factor analyses of the mammal fossils and sporopollen preserved in the cave sediments and of the vicarious paleoclimatic indexes such as the weathering index and the content of trace elements, the paleolclimatic cycles recorded in the cave sediments were quantitatively re-establised. Based on the age of Layer 2(410ka B.P.by TIMS) and the paleomagnetic B/M boundary measured in the upper part of Layer 14, Layers 1—14 of the cave sediments may be re-correlated with Stages 11—19 of the δ 18O curve of deep-sea cores of the S 4—S 7 series of the well-established loess-paleosol sequence in China. Furthermore, it is even possible to compare secondary climatic variations in each major paleoclimatic cycle.