江汉平原江陵地区9ka以来古气候演化的沉积记录  

Sedimentory records of paleoclimatic evolution in Jiangling,Jianghan Plain in the past 9 ka

作　　者：王秋良[1] 李长安[1] 谢远云[2] 

机构地区：[1]中国地质大学地球科学学院,武汉430074 [2]哈尔滨师范大学地理系,哈尔滨150080

出　　处：《湖泊科学》2006年第3期280-284,共5页Journal of Lake Sciences

基　　金：国家自然科学基金(40172061);国家重大基础研究项目(2003CB41520)联合资助

摘　　要：对江汉平原江陵剖面沉积物中的总有机碳(TOC)、总氮(TN)、有机碳同位素δ13C值和粒度参数的分布特征与环境气候的关系进行了研究．结果表明:沉积物中有机碳、总氮较高,有机质的δ13C值偏负,沉积物的平均粒径较粗时,气候温暖湿润;反之,沉积物中有机碳、总氮较低,有机质的δ13C值偏正,沉积物的平均粒径较细时,气候温凉偏干．结合14C测年,判别江汉平原江陵地区的古气候演化过程:8900-6070 aBP,为温湿时期;6000-4600 aBP为相对冷干时期;4600- 2500 aBP为温暖湿润时期;2500 aBP以来为温凉偏干时期．We analyzed the characteristics of organic matter TOC,TN and δ^13C value and sand sediment grain size from samples of Jianghan Plain and discussed its relationship with climatic circumstance. The results show that： the TOC and TN of the organic materials in sediments are higher, but the δ^13C are lower and grain sizes are coarser during warmer and wetter climatic episodes, On the other hand, during colder and dryer climatic episodes, the TOC and TN contents in sediments are lower. The δ^13C are lower and grain sizes are finer. With the results we reconstructed the evolution sequence of paleoelimate in Jianghan Plain region since 9000 aBP. It has four stages as follows ： 8900 - 6070 aBP, warm and wet; 6070 - 4600 aBP, cold and dry; 4600 - 2500 aBP, warm and wet; 2500 -500 aBP,cool and dry.

关 键 词：有机碳 有机碳同位素 粒度 古气候 江汉平原 

分 类 号：P532[天文地球—古生物学与地层学] X55[天文地球—地质学]