干旱区生态环境知识资源中心(Arid): The paleoenvironmental evolution of the Cambrian Longwangmiao Formation (Stage 4, Toyonian) on the Yangtze Platform, South China: Petrographic and geochemical constrains

Arid

DOI	10.1016/j.marpetgeo.2018.10.022
	The paleoenvironmental evolution of the Cambrian Longwangmiao Formation (Stage 4, Toyonian) on the Yangtze Platform, South China: Petrographic and geochemical constrains
	Ren, Ying 1; Zhong, Dakang 2; Gao, Chonglong 2; Li, Bing 2; Cao, Xuan 2; Wang, Ai 2; Dong, Yuan 2; Yan, Ting 3
通讯作者	Zhong, Dakang
来源期刊	MARINE AND PETROLEUM GEOLOGY
ISSN	0264-8172
EISSN	1873-4073
出版年	2019
卷号	100 页码:391-411
英文摘要	During the Cambrian Period Stage 4, biodiversity and biomass declined rapidly and globally in an event known as the Botomian-Toyonian crisis. To gain a better understanding of the paleoenvironment in South China during this stage, we present and interpret complex multi-parameter carbonate analyses (petrography, carbon and oxygen isotopic composition, and major, trace, and rare earth elements) from the Toyonian Longwangmiao Formation in the Bandenggou section. The Longwangmiao Formation comprises primarily carbonate deposits, with massive detrital mineral occurrences in its lower-middle sequence. Principal component analysis of the minerals and oxides leads to the definition of two intervals, I and II. Interval I is composed mainly of dolostones interbedded with sandstones and contains exceedingly high amounts of terrestrial original minerals and oxides, as well as high FREE + Y, Th, and Sc concentrations. Interval II, which is composed primarily of limestones, has trace amounts of terrestrial original minerals and oxides and low TREE + Y, Th, and Sc concentrations. The delta C-13 and delta O-18 values show a significant positive shift from Interval I to Interval II. After eliminating the effects of diagenesis contributions through the analyses of diagenesis sensitive indexes (delta O-18 values, MgO/CaO, Mn/Sr and Fe/Sr ratios, and the correlations of delta C-13-delta O-18, delta O-18-Eu/Eu, Eu/Eu-Ce/Ce* and Eu/Eu*-FeO), the Sr and Na concentrations of calcites in Interval I are extremely high, exceeding even the corresponding ranges of marine aragonites, while calcites from Interval II have low Sr and Na concentrations that are within the range of marine low-Mg calcite; however, both show strong positive correlations between Ca-Sr, Ca-Na, and Sr-Na. The different calcite elemental behaviors in Intervals I and II suggest different carbonate precursors associated with seawater temperature and climate. Furthermore, the Sr/Ca ratios are negatively correlated with delta C-13 and delta O-18 values, and the delta C-13 values also negatively correlated with SiO2 content. These features indicate a significant change in the depositional environment during the Cambrian Toyonian Stage from an early restricted marine environment under a warm and arid climate with massive terrestrial influxes to a later relatively open marine environment under a cool and humid climate with negligible terrestrial influxes; this shift likely resulted in the observed changes in biomass and biodiversity.
英文关键词	Carbonate geochemistry Paleotemperature Paleoclimate Terrestrial detritus influx
类型	Review
语种	英语
国家	Peoples R China
收录类别	SCI-E
WOS记录号	WOS:000458221100026
WOS关键词	RARE-EARTH-ELEMENTS ; MULTICOMPONENT CARBONATE SYSTEM ; DEVONIAN PRESQUILE BARRIER ; 3 GORGES AREA ; TRACE-ELEMENT ; ISOTOPE STRATIGRAPHY ; MARINE CARBONATE ; GLOBAL CLIMATE ; DELTA-C-13 EXCURSIONS ; CHEMICAL DIAGENESIS
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/217544
作者单位	1.Notheast Petr Univ, Coll Geosci, Daqing 163318, Heilongjiang, Peoples R China; 2.China Univ Petr, Coll Geosci, Beijing 102249, Peoples R China; 3.PetroChina, Tarim Oilfield Co, Res Inst Petr Explorat & Dev, Korla 841000, Xinjiang, Peoples R China
推荐引用方式 GB/T 7714	Ren, Ying,Zhong, Dakang,Gao, Chonglong,et al. The paleoenvironmental evolution of the Cambrian Longwangmiao Formation (Stage 4, Toyonian) on the Yangtze Platform, South China: Petrographic and geochemical constrains[J],2019,100:391-411.
APA	Ren, Ying.,Zhong, Dakang.,Gao, Chonglong.,Li, Bing.,Cao, Xuan.,...&Yan, Ting.(2019).The paleoenvironmental evolution of the Cambrian Longwangmiao Formation (Stage 4, Toyonian) on the Yangtze Platform, South China: Petrographic and geochemical constrains.MARINE AND PETROLEUM GEOLOGY,100,391-411.
MLA	Ren, Ying,et al."The paleoenvironmental evolution of the Cambrian Longwangmiao Formation (Stage 4, Toyonian) on the Yangtze Platform, South China: Petrographic and geochemical constrains".MARINE AND PETROLEUM GEOLOGY 100(2019):391-411.