关中盆地东部北刘剖面全新世大暖期气候高分辨率研究  

The high resolution climatic study of the holocene megathermal in Beiliu Profile in Eastern Guanzhong Basin

作　　者：徐勤向[1] 党群[2] 庞奖励[1] 

机构地区：[1]陕西师范大学旅游与环境学院,陕西西安710062 [2]陕西科技大学管理学院,陕西西安710054

出　　处：《固原师专学报》2005年第3期45-49,共5页Journal of Guyuan Teachers College

基　　金：陕西省自然基金(2003D01)资助.

摘　　要：通过对渭南北刘村黄土剖面的野外考察和粒度、磁化率、碳酸钙的分析,探讨了该地区全新世大暖期气候的高分辨率变化.研究结果显示该剖面较好地记录了全新世大暖期几次气候恶化事件,表明全新世大暖期气候并不是一直稳定的,而存在着气候的波动.6000-5000 a B.P.的气候干旱事件在该剖面有明显的反映,说明了该气候恶化事件普遍存在于关中盆地地区并且将大暖期分成了两个阶段,即大暖期早期暖湿阶段和大暖期晚期暖湿阶段.运用磁化率和碳酸钙淀积深度尝试着推算出了大暖期早晚阶段的年平均气温和降水,数据表明大暖期早期阶要比晚期阶温暖湿润的多.同时,粒度与磁化率指标显示在大暖期早晚温湿阶段还存在着次一级的气候恶化事件,如干旱、尘暴等.Field investigations, grain-size analysis, magnetic susceptibility and CaCO3 measurement in the loess profile of Beiliu, shanxi, have revealed the high resolution climatic change . The Result indicated that the Holocene Megathermal climate is unstableness and there are several times dried events. The dried event during 6000-5000 a B. P. exist obviously in the profile and divide the Holocene Megathermal into two parts. The average air temperature and precipitation per year is attempted to calculate by means of magnetic susceptibility and the illuvial death of the CaCO3. The data show that the early period of the Holocene Megathermal is more warm - humid than the late period. Simultaneously, the climatic proxy of grain -size analysis, magnetic susceptibility indicate that there are hypo-climate deteriorated in the warm-humid period of the Holocene Megathermal

关 键 词：气候变化 黄土 全新世大暖期 关中盆地 

分 类 号：P461[天文地球—大气科学及气象学]