干旱区生态环境知识资源中心(Arid): 新疆孔雀河北岸湖相沉积物稀土元素丰度特征及其古气候意义

Arid

	新疆孔雀河北岸湖相沉积物稀土元素丰度特征及其古气候意义
其他题名	Rare earth elements abundances of lake sediments in the northern margin of Kongque River,Xinjiang province and the paleoclimate significance
	白友良; 李博
来源期刊	干旱区资源与环境
ISSN	1003-7578
出版年	2019
卷号	33 期号:6 页码:113-118
中文摘要	通过对罗布泊LX02剖面孔沉积物稀土元素丰度、分布模式及稀土总量的分析,结合沉积物中烧矢量和粒度参数的变化特征,探讨了稀土元素纵向变化与气候环境之间的关系。结果表明:罗布泊沉积物中稀土元素丰度值较高,平均值为140. 0402mug /g ,总体上以较湿润的环境为主导,化学风化作用较强。同时,沉积物中轻重稀土元素比值约为9. 5,轻稀土含量明显高于重稀土含量,为明显的右倾斜型,Eu为中度负异常,Ce绝大部分为微弱的负异常的稀土配分模式。稀土元素含量与粒度和烧矢量之间存在较好的相关性,分析表明,沉积物中SigmaREE高值段指示暖湿气候环境,SigmaREE低值段代表冷干气候环境。根据稀土元素分布与沉积环境的关系,重建了72. 4 ~ 51. 0ka BP期间罗布泊地区经历了4次较大的冷干-暖湿-冷干-暖湿的气候演化过程,从而得出在干旱半干旱地区的罗布泊沉积物中稀土元素对古气候变化具有良好的指示作用。
英文摘要	Rare earth elements ( REE) are the good indicators for studying the provenance,paleoenvironment and paleoclimate of lake sediments due to their stable geochemical characteristics,and thus have important research significance. A 5. 4-m-thick section of lake sediments( 89°55’, 40°40’) was researched in the northern margin of the Kongque River,and the study area is located in Tarim town,Yuli county,southern Xinjiang Province. Based on the analysis of REE concentration and distribution vertical distribution of total REE,combined with the variation of loss-on-ignition and particle-size parameter in sediments,the relationship between REE and the climate and environment was discussed. The results show that REE values in the sediments are higher, with an average of 140. 0402mug /g, indicating that the humid environment was dominant with a more intense chemical weathering. The ratio of light rare earth elements ( LREE) /heavy earth elements ( HREE) is 9. 5,indicates that the LREE is rich and the HREE is poor. The sediments from LX02 profile have very similar REE distribution patterns,which are rich in LREE,with negative slopes and moderate negative Eu anomaly and weak negative Ce anomaly. Total REE contents have good relationships with loss-on-ignition and particle-size parameters. During warmer and wetter climatic episodes,the values of total REE in sediments are higher; on the contrary,during colder and drier climatic episodes,the values of total REE are lower. The further study has reconstructed the paleoclimate evolution of Lop Nor area since 72. 4kaBP,which includes four main climatic and environmental changes that were cool-dry,warm-moist and cold-dry warm-moist,during Late-Pleistocene period. Finally,we concluded that REE in sediments of Lop Nor area is an effective indicator to reconstruct the paleoclimatic variation in the semi-arid areas because of its sensitivity to the climatic changes.
中文关键词	古气候 ; 稀土元素丰度 ; 冷干-暖湿气候 ; 孔雀河 ; 新疆
英文关键词	paleoclimate rare earth element abundances dry-cold and humid-warm climate Kongque River Xinjiang
类型	Article
语种	中文
国家	中国
收录类别	CSCD
WOS类目	Geology
WOS研究方向	Geology
CSCD记录号	CSCD:6485153
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/239201
作者单位	白友良, 西北核技术研究所, 西安, 陕西 710024, 中国.; 李博, 西北核技术研究所, 西安, 陕西 710024, 中国.
推荐引用方式 GB/T 7714	白友良,李博. 新疆孔雀河北岸湖相沉积物稀土元素丰度特征及其古气候意义[J],2019,33(6):113-118.
APA	白友良,&李博.(2019).新疆孔雀河北岸湖相沉积物稀土元素丰度特征及其古气候意义.干旱区资源与环境,33(6),113-118.
MLA	白友良,et al."新疆孔雀河北岸湖相沉积物稀土元素丰度特征及其古气候意义".干旱区资源与环境 33.6(2019):113-118.