干旱区生态环境知识资源中心(Arid): 柴达木盆地SG-1孔1.0Ma以来碳酸盐同位素记录的亚洲内陆干旱化及成因

Arid

	柴达木盆地SG-1孔1.0Ma以来碳酸盐同位素记录的亚洲内陆干旱化及成因
其他题名	ARIDIFICATION OF THE ASIAN INLAND SINCE 1.0Ma:EVIDENCES FROM CARBONATE ISOTOPE RECORDS OF DEEP CORE FROM THE QAIDAM BASIN
	滕晓华 1; 韩文霞 2; 叶程程 3; 张志高 4; 彭文彬 4; 方小敏 5
来源期刊	第四纪研究
ISSN	1001-7410
出版年	2013
卷号	33 期号:5 页码:866-875
中文摘要	亚洲内陆干旱区是连接赤道和中高纬地区的过渡地带,也是西风气候和季风气候的相互作用区,其形成演化与青藏高原的隆起和全球变化等因素密切相关。因此,揭示其干旱化过程和趋势具有重大的理论和现实意义。文章对来自柴达木盆地察汗斯拉图干盐湖的深钻SG-1孔沉积物进行了初步的碳酸盐碳氧同位素测试与分析,结果清晰地指示了柴达木盆地自1.0Ma以来的持续干旱化及约0.6Ma以来的加速干旱化过程,我们认为1.0Ma以来的持续干旱化可能是全球气候变化和构造活动共同作用的结果,而约0.6Ma以来的加速干旱化可能是昆黄运动所导致的高原北部强烈隆升和区域环流系统变化或强化所造成的。
英文摘要	As the largest temperate arid region,the vast Asian arid inland has attracted wide interests due to its great impacts on global climatic change.However,its evolution history and its relation with the westerlies,Tibet uplifts and global change are still unknown.Although many related studies have been carried out,most of the studies are mainly based on the eolian records from the surrounding areas,and only few records are directly from this arid region. The Qaidam basin,located in the eastern part of this vast arid region,develops continuous and well-exposed Cenozoic sediments,providing a unique opportunity to study aridity of the Asian inland.We obtained a 938.5m long lake sediment core(SG-1)(38°24’35.3"N,92°30’32.6"E;2700m a.s.l.)with an average recovery rate of 95% from the saline playa in the depocenter of the Chahansilatu sub-basin between the Eboliang anticline and the Jianshan anticline in the western Qaidam basin.A combined detailed paleomagnetic dating, OSL and U series dating of the core determined its age at about 2.77Ma to 0.10Ma. The core is mainly comprised of evaporate-bearing fine mudstone-siltstone sequence.In the lower 390.0~938.5m part of the core,the sediments consist mainly of alternation of dark-gray or bluish-gray generally laminated mudstone and siltstone and gray calcareous mudstone and marl/limestone.In the upper 0~390m part of the core,the lithology is characterized by cycles of thick gray-white salt and grayish black massive-laminated mudstone-siltstone mostly containing gypsum crystals or thin gypsum layers.This study mainly carries out a more detailed analysis of carbon and oxygen isotopes for the upper 0~350m part of the core with 0.1~1.0Ma.Samples with high carbonate contents (>30wt%) were systematically collected at an average interval of ca.3m and 135 samples were selected.We collected 12 rock samples(including limestone and marble)from exposed strata since Precambrian in the surrounding Kunlun,Qilian and Altun major river basins to determine the carbon and oxygen isotopes in lakes debris and further to learn whether the lake debris can effect the isotopes of the lacustrine carbonate.All samples were first oven-dried at 40℃ and ground into fine powder.After standard routine of treatment,the carbon isotope and oxygen isotope results were analyzed using a MAT -252 Mass Spectrometer,with a precision of better than 0.1. The analyses of stable isotopes of carbonates from the SG-1 core suggest that the carbonates in this core are authigenic and the oxygen isotope mainly reflects the regional aridity.The carbonate isotope records indicate that there exists an evident long-term persistent aridification of Asian inland since ca.1.0Ma,followed by an accelerated drying since ca.0.6Ma.The Qaidam paleo-lake changed from brackish lake to salt lake and finally playa accordingly. From 1.0Ma to 0.6Ma,the carbon and oxygen isotope values change from -1.4 to 3.7 and -2.9 to 3.9,respectively,indicating a minor drying trend.We speculate that both the northern hemisphere glaciation and the uplift of the Tibetan Plateau in the mid-Pleistocene(Kunhuang Movement)occurred at about 1.0Ma might have collectively prompted the drying of the Asian inland during this time. Since 0.6Ma,both the carbon and oxygen isotope values show sharp synchronous increasing trends(changed from -0.6 to 7.3 and -1.7 to 11.9,respectively),which are discordant with the marine oxygen isotope records.We suggest that the rapid uplift of the Tibetan Plateau(Kunhuang Movement C)might have contributed to the aridification of the Asian inland through changing or enhancing the westerly jet and blocking the moisture input from the westerlies and monsoons.
中文关键词	干旱化 ; 亚洲内陆 ; 碳酸盐碳氧同位素 ; 柴达木盆地 ; 西风环流
英文关键词	aridification Asian inland carbonate isotope Qaidam basin Westerlies
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY ; GEOSCIENCES MULTIDISCIPLINARY
WOS研究方向	Geology
CSCD记录号	CSCD:4944958
来源机构	兰州大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/229428
作者单位	1.兰州大学西部环境与气候变化研究院, 西部环境教育部重点实验室;;中国科学院盐湖资源与化学重点实验室, 兰州, 甘肃 730000, 中国; 2.中国科学院青海盐湖研究所, 中国科学院盐湖资源与化学重点实验室, 西宁, 青海 810008, 中国; 3.中国科学院青藏高原研究所, 中国科学院大陆碰撞与高原隆升重点实验室, 北京 100101, 中国; 4.兰州大学西部环境与气候变化研究院, 西部环境教育部重点实验室, 兰州, 甘肃 730000, 中国; 5.兰州大学西部环境与气候变化研究院, 西部环境教育部重点实验室;;中国科学院大陆碰撞与高原隆升重点实验室, 兰州, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	滕晓华,韩文霞,叶程程,等. 柴达木盆地SG-1孔1.0Ma以来碳酸盐同位素记录的亚洲内陆干旱化及成因[J]. 兰州大学,2013,33(5):866-875.
APA	滕晓华,韩文霞,叶程程,张志高,彭文彬,&方小敏.(2013).柴达木盆地SG-1孔1.0Ma以来碳酸盐同位素记录的亚洲内陆干旱化及成因.第四纪研究,33(5),866-875.
MLA	滕晓华,et al."柴达木盆地SG-1孔1.0Ma以来碳酸盐同位素记录的亚洲内陆干旱化及成因".第四纪研究 33.5(2013):866-875.