干旱区生态环境知识资源中心(Arid): 西藏洞错硼砂芒硝层的发现及其古气候意义

Arid

	西藏洞错硼砂芒硝层的发现及其古气候意义
其他题名	Discovery of Borax-bearing Mirabilite Beds in Tontso Lake, the Northern Tibet and Its Palaeoclimatic Significance
	魏乐军 1; 郑绵平 2; 刘喜方 2; 蔡克勤 3; 乜贞 2
来源期刊	地质学报
ISSN	0001-5717
出版年	2002
卷号	76 期号:2 页码:261-271
中文摘要	通过调查藏北高原腹地盐湖－洞错的1级阶地湖相化学沉积，首次发现硼砂及赋存5层纯芳硝层的完整沉积剖面，依剧韵律层的沉积特征研究和~(14)C测年，针对剖面中出现的冷相盐类矿物－－芳硝，应用比较盐湖学的理论经和方法，指出洞错在全新世早、中期经历了潮湿温暖期(> 8470 a BP，可能至10500 a BP)寒冷干旱期(8470～8170 a BP)潮湿温暖期(8170～7590 a BP)气候频繁波动期(7590～7400 a BP，寒冷大背景下三干三湿的气候演替)寒冷干旱期(7400～6940 a BP)潮湿温和期(6940～6620 a BP)寒冷干旱期(6620～6410 a BP)温暖湿润期(6410 a BP以后)的演变序列。
英文摘要	The Tontso, a saline lake at the center of the northern Tibetan Plateau, was chosen as a study object, Modern chemical sediments are forming in the lake without human-induced pollution. Borax in the mirabilite beds was discovered in the second bottom of the Tontso lake and a sedimentary sections with five layers of pure mirabilite was seen. This is significant for the appraisal of resources and prospecting in the area as well as palaeoclimatic and palaeoenvironmental study. Research on the five layers of mirabilite and the whole section with comparative salinology of saline sedimentary environment study confirmed that, as a cold saline mineral, mirabilite is a delicate and effective indicator for reconstructing palaeoclimate and palaeoenvironment. High-resolution analyses based on reliable age scale sensitively rebuilt the palaeoclimatic environment in which saline chemical sediments were formed. It is pointout that, during the early-middle Holocene (>8470～6410 a BP), a series of dry/wet and cold/warm climate changes occurred as fellows: >8470 a BP, probable to 10500 a BP: generally warm & wet. 8470～8170 a BP: frigid & arid (lasting 300 a). 8170～7590 a BP: warm & wet (lasting 580 a). 7590～7400 a BP: frequently fluctuating (lasting 190 a). Under frigid background, a fluctuating climate of three arid and three wet periods alternating. 7400～6940 a BP: frigid & arid (lasting 540 a). 6940～6620 a BP: warm & slightly wet (lasting 320 a). 6620～6410 a BP: frigid & arid (lasting 210 a). After 6410 a BP: generally warm & wet (As the upper part of sections did not appear in this climate, the lasting time of the stage cannot be determined). The palaeoclimatic environment is fully comparative and consistent with that revealed in the synchronous records of neighbouring lakes, e.g., the retreating trace and pollen in the Chabyer Cake, drilling data in the Bangkog Co, the delta~(18)O value in Siling Co, pollen and diatom in Lungmu Co and Sumxi Co, and the Quaternary spreading of Stage V of arid climate (salinization) with the Qaidam-eastern Tarim area as the center in western China. Meanwhile, with high precision of sections from the Tontso, the palaeoclimate and palaeoenvironment of this period can be divided in more detail.
中文关键词	西藏洞错 ; 硼砂芳硝层 ; 全新世 ; 气候变化
英文关键词	Tontso lake borax-bearing mirabilite palaeoclimate Holocene Xijiang (Tibet)
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:972881
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/203122
作者单位	1.中国地质科学院矿产资源研究所, 北京 100037, 中国; 2.中国地质科学院矿产资源研究所, 盐湖资源与环境开放研究实验室, 北京 100037, 中国; 3.中国地质大学(北京), 北京 100083, 中国
推荐引用方式 GB/T 7714	魏乐军,郑绵平,刘喜方,等. 西藏洞错硼砂芒硝层的发现及其古气候意义[J],2002,76(2):261-271.
APA	魏乐军,郑绵平,刘喜方,蔡克勤,&乜贞.(2002).西藏洞错硼砂芒硝层的发现及其古气候意义.地质学报,76(2),261-271.
MLA	魏乐军,et al."西藏洞错硼砂芒硝层的发现及其古气候意义".地质学报 76.2(2002):261-271.