检索结果-南通市图书馆

Sedimentological Characterization of Alluvial Gold Deposits of Betrare-Oya and Its Surroundings (Cameroon Eastern Region)

引用

International Journal of Geosciences 2020年第12期11卷 783-799页

作者： Daniel Mackaire Eloung Nna paul desiré ndjigui Joseph Quentin Yene Atangana Alexis Jacob Nyangono Abolo Constantin Maurice Ndongue Department of Earth Sciences University of Yaounde I-Cameroon Yaounde Cameroon Faculty of Mines and Petroleum Industries University of Maroua-Cameroon Maroua Cameroon

Sedimentological methods such as granulometry, morphoscopy and heavy minerals analysis have been carried out to characterize alluvial gold deposits of Betare-Oya and its surroundings, with the aim to determine their origin and conditions in which they are formed and also to determine the mineralogical content of these deposits, their nature and distribution. It came out from this study the following: The alluvial deposits studied are sand, constituting of coarse fraction (grains), medium grains in abundant and fine grains. The average values of sorting index (S0) and coefficient of asymmetry (A) are respectively 2.53 and 0.73. These values indicate that the sand is poorly arranged and poorly sorted with a better classification or arrangement in the coarse fraction (grains). These are sediments that are deposited together by high competent currents. It would therefore probably be torrential deposits and or streams from short transport. Unused grains are dominating (80.5%) which translate a proximal source of the sediments. So it would be probably from the dismantling of the surrounding landforms. The heavy minerals studied revealed the presence of the following minerals;zircon, gold, sphene, green hornblende, tourmaline, rutile, augite, hypersthene, sillimanite, glau-cophane, biotite, staurotide, and the opaque. These minerals belong to the cortege of plutonic and metamorphic rocks from a single proximal distributing province.

关键词： Betare-Oya and Its Surroundings Alluvial Gold Deposits Granulometry Morphoscopy Heavy Minerals Polished Sections

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mineralogy and geochemistry of the Ngaoundaba Crater Lake sediments,northern Cameroon:implications for provenance and trace metals status

引用

Acta Geochimica 2021年第5期40卷 718-738页

作者： Armel Zacharie Ekoa Bessa John SArmstrong-Altrin Gentry Calistus Fuh Thierry Bineli Betsi Tebogo Kelepile paul-desirendjigui Department of Earth Sciences University of Yaounde IP.O.Box 812YaoundeCameroon Universidad Nacional Autonoma de Mexico Instituto de Ciencias del Mar Y LimnologıaUnidad de Procesos Oceanicos y CosterosCircuito exterior s/n04510 MexicoD.F.Mexico Department of Mining and Geological Engineering Botswana International University of Sciences and TechnologyPrivate Bag 16PalapyeBotswana

This study was conducted on the Ngaoundaba Crater Lake sediments to infer provenance,weathering conditions,organic matter accumulation,and trace metal *** Lake sediments were collected using a manual core sampler at 5 to 8 m water *** sediment cores from the littoral and center of the lake were analyzed for grain size distribution,water content(WC),organic matter content,mineralogy,and major and trace element *** Ngaoundaba sediments were classified as silt and sandy *** show high content in organic matter,which is more to the littoral than to the center of the lake,varying from 14.6%to 24%and21.2%to 40.8%,*** grain surface features identified by Scanning Electron Microscopy(SEM)show both chemical and mechanical microtextures with subrounded to angular shape suggesting both proximal and distal *** lake sediments are composed of quartz,kaolinite,and hematite,with low amounts of feldspars,rutile,calcite,illite,and *** indices such as the chemical index of alteration(CIA),chemical index of weathering(CIW),and index of compositional variability(ICV)indicate moderate to intense chemical weathering in the source area and immature to mature *** geochemical composition indicates that the sediments were derived from felsic to intermediate igneous rocks,such as granitoids,and mafic alkali lavas like *** environmental risk assessment of trace metals obtained by enrichment factor(EF)and geo-accumulation index(I-geo)shows low contamination of the lake sediments.

关键词： Ngaoundaba Crater Lake Mineralogy Geochemistry Provenance Metal traces status

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

Water Quality Assessment in the Bamoun Plateau, Western-Cameroon: Hydrogeochemical Modelling and Multivariate Statistical Analysis Approach

引用

Journal of Water Resource and Protection 2021年第2期13卷 112-138页

作者： Zakari Mfonka Amidou Kpoumié Abdou Nasser Ngouh Oumar Farouk Mouncherou Daouda Nsangou Felaniaina Rakotondrabe Alain Fouépé Takounjou Mounira Zammouri Jules Rémy Ndam Ngoupayou paul-Désiré ndjigui Geosciences Natural Resources and Environment Laboratory Department of Earth Sciences Faculty of Science University of Douala Douala Cameroon Geosciences and Sustainable Development Laboratory Department of Earth Sciences Faculty of Science University of Maroua Maroua Cameroon National Institute of Cartography Ministry of Scientific Research and Innovation Yaoundé Cameroon Institute for Geological and Mining Research Ministry of Scientific Research and Innovation Yaoundé Cameroon Geosciences of Superficial Formations and Applications Laboratory Department of Earth Sciences Faculty of Science University of Yaoundé I Yaounde Cameroon Center of Water Research and Technologies Geo-Resources Laboratory Faculty of Science University of Tunis El Manar Tunis Tunisia

This study focuses on the geochemical and bacteriological investigation of surface and ground water in the Bamoun plateau (Western-Cameroon). During the period from September 2013 to August 2014, 71 samples were collected from two springs, one borehole, four wells and the Nchi stream for analysis of major elements. In order to obtain the characteristics of the various species of bacteria, 7 samples were selected. The analytical method adopted for this study is the conventional hydrochemical technic and multivariate statistical analysis, coupled with the hydrogeochemical modelling. The results revealed that, water from the zone under study are acidic to basic, very weakly to weakly mineralized. Four types of water were identified: 1) CaMg-HCO3;2) CaMg-Cl-SO4;3) NaCl-SO4 and 4) NaK-HCO3. The major elements were all listed in the World Health Organization guidelines for drinking water quality, except for nitrates which was found at a concentration > 50 mg /l NO-3 in the borehole F401. As for the hydrobiological aspect, the entire sample contained all the bacteriological species except for spring S301 and well P401. According to the hydrogeochemical modelling, the Gibbs model and multivariate statistical tests, the quality of surface and ground water of the Foumban locality is influenced by two important factors: 1) the natural factors characterized by the water-rock interaction, evapotranspiration/crystallization, 2) the anthropogenic factors such as: uncontrolled discharges of liquid and solid effluents of all kinds and without any prior treatment within the ground and the strong urbanization accompanied by lack of sanitation and insufficient care.

关键词： Foumban Surface and Ground Water Water-Rock Interaction Bacteriological Parameters Hierarchical Clustering Analysis Principal Component Analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

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

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

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：