干旱区生态环境知识资源中心(Arid): 湘西寒武系鼓山阶底界附近碳同位素组成演化趋势

Arid

	湘西寒武系鼓山阶底界附近碳同位素组成演化趋势
其他题名	Carbon isotope trend around the base of the Drumian Stage in western Hunan, South China
	左景勋 1; 彭善池 2; 朱学剑 2; 方怀宾 1; 祁玉平 2; 陈泳霖 1
来源期刊	地球化学
ISSN	0379-1726
出版年	2018
卷号	47 期号:5 页码:453-462
中文摘要	湘西王村剖面寒武系鼓山阶(Drumian)底界附近碳酸盐岩的delta~(13)C值分布于0.5~ -3.0之间, delta~(18)O值分布于-4.0 ~ -12.0之间,少数碳酸盐岩样品的delta~(18)O值低于-10.0,指示岩石经历成岩期后蚀变作用影响,但delta~(13)C、delta~(18)O之间的非协变关系指示碳同位素组成比较稳定。鼓山阶底界附近delta~(13)C表现为负漂移演化趋势,负漂移幅度为4.0,最低值出现在鼓山阶底界之上9 m处,与美国犹他州Drum Mountains剖面鼓山阶负漂移(DICE)出现的位置基本一致,负漂移幅度可与美国内华达州Desert Range剖面、Panaca Hills剖面、犹他州House Range剖面、Drum Mountains剖面对比,表明DICE负漂移具有洲际可对比性,可作为寒武系鼓山阶划分与对比的工具。湘西王村剖面寒武系第二统顶部清虚洞组、第三统底部敖溪组白云岩为海平面下降期形成的进积序列,寒武系第三统花桥组下部黑色泥灰岩、钙质泥岩夹富含黄铁矿结核的硅质条带为深水斜坡相沉积,超覆于白云岩之上。因此,寒武系鼓山阶底部附近的DICE负漂移发生在寒武纪第三世鼓山期海侵时期,与美国Drum Mountains剖面鼓山阶DICE负漂移所处的沉积环境相似。
英文摘要	The delta~(13)C of carbonate samples collected around the base of the Drumian Stage in the Wangcun section, western Hunan, South China, ranged from 0.5 to -3.0, and delta~(18)O values ranged from -4.0 to -12.0. A few carbonate samples had delta~(18)O values of less than -10.0, thereby indicating that the carbonates experienced diagenesis. However, values of delta~(13)C and delta~(18)O showed no covariance, which implied that the carbon isotopic composition is relatively stable. One negative carbon isotope excursion was detected around the base of the Drumian Stage of the Cambrian. Moreover, the amplitude of this negative excursion was 4.0 and the minimum value of delta~(13)C occurred at 9 m above the base of the Drumian Stage, and all these characteristics were similar to the negative DICE (Drumian carbon isotope excursion) tested in the Drum Mountains section in Utah, USA. The range in delta~(13)C varied, and the position where the carbon isotope excursion occurred in the Wangcun section in western Hunan, South China could be compared with that in the Panaca Hills section and the Desert Ridge section in Utah, as well as the House Range section and the Drum Mountains section in Utah, USA, thereby suggesting that the negative DICE can be used as an indicator for correlation between the Drumian Stage in different continents. In addition, dark marl limestone and calcareous mudstone containing tubular pyrite in siliceous ribbons in the lower part of the Huaqiao Formation were deposited on a deep-water ramp during sea-level rise. In contrast, dolomite of the Qingxudong Formation in the upmost part of Series 2 and dolomite of the Aoxi Formation in the basal part of Series 3 were deposited during sea-level fall. Consequently, the negative DICE occurred in a transgressive succession in early Epoch 3 at the Wangcun section in western Hunan, South China, which is similar to that in the Drum Mountains section in Utah, USA.
中文关键词	碳同位素组成 ; DICE负漂移 ; 鼓山阶 ; 寒武系 ; 湘西王村
英文关键词	carbon isotopic composition DICE negative excursion Drumian Stage Cambrian Wangcun section in Western Hunan
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:6333159
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/237431
作者单位	1.河南省地质调查院, 郑州, 河南 450001, 中国; 2.中国科学院南京地质古生物研究所, 南京, 江苏 210008, 中国
推荐引用方式 GB/T 7714	左景勋,彭善池,朱学剑,等. 湘西寒武系鼓山阶底界附近碳同位素组成演化趋势[J],2018,47(5):453-462.
APA	左景勋,彭善池,朱学剑,方怀宾,祁玉平,&陈泳霖.(2018).湘西寒武系鼓山阶底界附近碳同位素组成演化趋势.地球化学,47(5),453-462.
MLA	左景勋,et al."湘西寒武系鼓山阶底界附近碳同位素组成演化趋势".地球化学 47.5(2018):453-462.