检索结果-南通市图书馆

Primary dolostone related to the Cretaceous lacustrine hydrothermal sedimentation in Qingxi sag, Jiuquan Basin on the northern Tibetan Plateau

引用

Science China Earth Sciences 2013年第4期56卷 2080-2093页

作者： WEN HuaGuo ZHENG RongCai QING HaiRuo FAN MingTao LI YanAn GONG BoShi State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Institute of Sedimentary Geology Chengdu University of Technology Department of Geology University of Regina Yumen Oilfield Company of PetroChina

Based on comprehensive studies in petrography, petrofabric analysis and geochemistry, this paper describes a unique and rare laminated micritic ferruginous primary dolostone crystallized and precipitated from the alkaline hot brine under the conditions of the Mesozoic faulted lake basin. The main rock-forming mineral of this dolostone is ferruginous dolomite with a micritic structure. This dolomite mostly exhibits laminae of 0.1-1 mm thick and is often discovered with other minerals, such as albite, analcite, barite and dickite, which have at least two types of interbedded laminae. Petrogeochemistry reveals that this dolostone contains a large number of typomorphic elements of hydrothermal sedimentation, including Sb, Ba, Sr, Mn, and V. In addition, the LREE is in relatively high concentrations and possesses the typical REE distribution pattern with negative Eu anomaly. Oxygen isotope values （C^ISOpDB） range from 5.89%~ to 14.15%o with an average of 9.69%0. The ratio of 87Sr/86Sr is between 0.711648 and 0.719546, with an average of 0.714718. These data indicate that the depositional environment is a stable, blocked, anoxic low-lying hot brine pool in the bottom of deep lake controlled by basement faults. The hydrothermal fluid is the alkaline hot brine formed by the combination of the infiltration lake water and mantle-derived magmatic water, consisting of many ions, including Ca2＋, Mg2＋ and Fe2＋. Under the driving flow power of magmatic heat, gravity and compaction, the hy- drothermal fluid overcame the overburden pressure and hydrostatic pressure of the lake water body, and boiled to explosion, and then the explosion shattered the original laminated micritic ferruginous primary dolostone near the vent and then formed a new type of dolostone called shattered ＂hydroexplosion breccias＂. In the low-lying, unperturbed hot brine pool, far from the vent, the laminated micritic ferruginous primary dolostone was quickly crystallized and chemicals precipitated from the hy-

关键词： primary ferruginous dolostone hydrothermal sedimentation fault lakes Cretaceous Jiuquan Basin

来源：

维普期刊数据库

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

New Evidence for hydrothermal Sedimentary Genesis of the Ni-Mo Deposits in Black Rock Series of the Basal Cambrian, Guizhou Province: Discovery of Coarse-Grained Limestones and its Geochemical Characteristics

引用

Acta Geologica Sinica(English Edition) 2012年第3期86卷 579-589页

作者： WEI Huairui YANG Ruidong GAO Junbo CHEN Jiyan LIU Kun CHENG Wei College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550003Guizhou ProvinceChina

The molybdenum-nickel deposits in Shuidong District of Nayong County （Guizhou Province, Southwest China） are found mainly in black shale series of Lower Cambrian Niutitang Formation, which is another Mo-Ni-rich region besides Zunyi District （Guizhou province）. Our systematic study on the Mo-Ni deposits in Tangjiaba of Nayong reveals that layered coarse-grained limestones, spherical beaded limestones concretions are hosted at the lower seam of the Mo-Ni deposits. Its strong negative carbon isotope anomaly （the carbon isotope value of the coarse-grained limestones varies from -2.148‰ to 8.223‰） is similar to that in the modern submarine black smoker chimney. The carbon in the coarse-grained limestones from black rock series of Nayong County might be deep source inorganic carbon. The seams, coarse-grained limestones, ore-bearing coarse-grained limestones and the roof and floor of the deposits are characterized by co-variation on the trace element spider diagram, showing good homology. The extraordinary enrichment of Ag, As and Sb resembles hydrothermal sedimentation. Pro-Earth＇s core elements Se is strongly enriched in Ni-Mo ore-bearing coarse-grained limestones. The ore-bearing rock series has an extremely low Th/U value （0.012-0.19）; in the logU-logTh Cartesian Coordinates, the samples of the roof and floor of the deposits and ore-bearing coarse-grained limestones are found in the East Pacific tise; and the samples of coarse-grained limestones are found between the paleo-hydrothermal dedimentary area and the East Pacific tise. The chondrite-normalized rare earth element patterns of the Ni-Mo deposits show LREE enrichment, Ce negative anomaly, and Eu negative anomaly （which is supposed to be influenced by the deep magmatic processes in an extensional environment） resembles the rare earth element distribution patterns of the fluid and its sediments in modern submarine hydrothermal system. It proves that coarse-grained limestones is characterized by typical hydrothermal

关键词： Coarse-grained limestones geochemistry hydrothermal sedimentation black rock series Cambrian Nayong

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

GEOLOGICAL AND GEOCHEMICAL CHARACTERISTICS AND RELATED MINERALIZATION OF CHERT FORMATIONS IN SOUTH TIBET

引用

Geotectonica et Metallogenia 2005年第2期29卷 107-115页

作者： HE Junguo ZHOU Yongzhang YANG Zhijun NIE Fengjun FU Wei ZHANG Chengbo Center of Earth＇s Environment ＆ Resources Guangzhou GD 510275 China Dept. of Earth Sciences Zhongshan University Guangzhou GD 510275 china Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

There occur abundant cherts in the Mesozoic and Cenozoic strata in southern Tibet. Some of them possess characteristic hydrothermal structures such as layered, laminated, massive and breccia structures. Ratios of Al/（Al＋Fe＋Mn）, Co/Ni, Fe/Ti and TiO2-A1203 demonstrate that their origin is related to hydrothermal sedimentation. The chert formations have close relationship with Sb, Au and poly-metallic mineralization, and the ore-forming fluid show strong correlation with fossil hydrothermal water. There occur abundant cherts in the Mesozoic and Cenozoic strata in southern Tibet. Some of them possess characteristic hydrothermal structures such as layered, laminated, massive and breccia structures. Ratios of A1/（AI＋Fe＋Mn）, Co/Ni, Fe/Ti and TiO2-A1203 demonstrate that their origin is related to hydrothermal sedimentation. The chert formations have close relationship with Sb, Au and poly-metallic mineralization, and the ore-forming fluid show strong correlation with fossil hvdrothermal water.

关键词： chert sedimentary structure hydrothermal sedimentation metallic mineralization Southern Tibet

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A new exhalite type——siderite-sericite chert formed in fault-controlled lacustrine basin

A new exhalite type——siderite-sericite chert formed in fau...

引用

中国科学院地质与地球物理研究所2001学术年会

作者：刘建明叶杰张安立王玉往姜能 Institute of Geology and Geophysics Chinese Academy of Sciences Dajing Ag-Cu Mine Linxi CountyInner MongoliaLinxi County Town 025250China

On the basis of geological,fabric,lithographical and mineralogical study,a new exhalite type,called ’siderite-sericite chert’ according to its mineral assemblage,was reported for the first *** was formed in a fault-controlled lacustrine basin and closely associated with sulfide ore characteristic of complex metal assemblage of *** geological setting,mineral assemblage,as well as associated ores are quite unique,and therefore worthy of detailed research. In the Dajing deposit,Linxi County,Inner Mongolia,it is this very exhalite that is regarded as a kind of acidic subvolcanic dike till now,and because of this,a genetic model of hydrothermal epigenetic filling by subvolcanic fluid prevails over the Dajing *** is demonstrated again that any geochemical study might be senseless without support of detailed geological and lithographical *** is of particular importance at the present time when one is readily confused by various modern techniques.

关键词： hydrothermal sedimentation siderite-sericite chert geological-fabric study Inner Mongolia

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：