检索结果-南通市图书馆

Meso-Archean to Mid-Paleozoic Granitoids in Oulad Dlim Massif(the Pericratonic Terrane of the Reguibat Shield,West African Craton,Morocco):Petrology,Geochemistry,Geochronology and Geological Implications

引用

Journal of Earth Science 2022年第5期33卷 1152-1165页

作者： Haissen Faouziya Montero Pilar Molina Jose Francisco Lodeiro Francisco Mouttaqi Abdellah Chaib Mustapha Bea Fernando LGAGE Département de GéologieFacultédes Sciences Ben M’sikHassan II University of CasablancaB.P.5366MaarifCasablancaMaroc Department of Mineralogy and Petrology University of GranadaCampus FuentenuevaGranada18002Spain Office National des Hydrocarbures et des Mines 5 Avenue Moulay HassanRabatMaroc

The Oulad Dlim Massif,adjacent to the Reguibat Shield in South Morocco was considered up to now as part of the Variscan belt(Mauritanides)with a polyphase geologic history and a complex geodynamic evolution implicating oceans closures and accretion of exotic terranes(Avalonian and Meguman)during the Variscan-Alleghanian *** use of modern technology to characterize the petrology,the geochemistry and the geochronology of the lithological units forming this region,combined to field surveys has led to an updated geological architecture and different geological *** Oulad Dlim Massif is mainly a deformed Archean terrane,as recorded by its eastern and western sectors,dominated in its central part by a bimodal felsic-mafic magmatism forming the Ediacaran *** study of these magmatic complexes supports strongly the intracontinental origin of this bimodal magmatism *** oceanic origin published before in *** exploration of this massif conducted also to the identification of a Silurian-Devonian sector in the western ***,up to date,different magmatic events lasting from the Meso-Archean to the Cretaceous are recorded in the Oulad Dlim Massif rocks,among them different generations of granitoids are *** data on granitoids from the Ediacaran sector are presented in this *** recent data demonstrates that Oulad Dlim Massif has been affected by the main Ediacaran–Cambrian extensional event widely documented in other structural domains of Morocco and other parts of North ***,the study of the Silurian-Devonian sector rocks highlighted the presence of a Caledonian tectonic event challenging the ideas about the paleogeography of this part of northwestern Africa and its geological evolution during the ***,despite the significant contribution of this extensive survey and the abundance of data on the Oulad Dlim Massif,more studies are required to reconstruct the puzzle at plate tectonic scale.

关键词： Archean Ediacaran bimodal magmatism extension intracontinental rifting Caledonian tectonic event petrology geochemistry

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

Minto Large Igneous Province: A 2.00 Ga Mafic Magmatic Event in the Eastern Superior Craton Based on U-Pb Baddeleyite Geochronology and Paleomagnetism

引用

Acta Geologica Sinica(English Edition) 2016年第S1期90卷 69-70页

作者： Michael A.HAMILTON Jean GOUTIER Kenneth L.BUCHAN Jack Satterly Geochronology Lab Dept.of Earth Sciences University of Toronto Géologie Québec - Ministère de l'énergie et des Ressources naturelles Geological Survey of Canada

A precise U-Pb baddeleyite age of 1999±2 Ma has been obtained for the NNW trending Lac Shpogan dyke swarm of the James Bay area of the eastern Superior *** the age of the swarm was only

关键词： Pb A 2.00 Ga Mafic Magmatic Event in the Eastern Superior Craton Based on U-Pb Baddeleyite Geochronology and Paleomagnetism Minto Large Igneous Province Bay Ga

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

Late Devonian OIB Alkaline Gabbro in the Yarlung Zangpo Suture Zone:Remnants of the Paleo-Tethys?

引用

地学前缘 2009年第S1期16卷 273-273页

作者： Réjean Hébert Raoult Guillaume Rachel Bezard Département de Géologie et de Génie Géologique

The Yarlung Zangpo Suture Zone(YZSZ) is believed to be composed of material largely derived from the destruction of the Neo-Tethys *** report here geochronological and petrological data obtained for newly discovered alkaline gabbro blocks embedded in a m(?)lange zone of the YZSZ,in Zhongba area, southwestern *** gabbros are Late Devonian in age and of intra-oceanic Ocean Island Basalt(OIB) ***-zircon U-Pb analyses from one representative gabbro sample by SIMS(Secondary

关键词： Devonian Yarlung Zangpo suture Paleo-Tethys Southern Tibet SIMS

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

Evaluation of Water Resources Quality in Sabodala Gold Mining Region and Its Surrounding Area (Senegal)

引用

Journal of Water Resource and Protection 2015年第3期7卷 247-263页

作者： Mall Ibrahima Diaw Moctar Dieng Ndèye Maguette Madioune Hélène Diakher Ngom Papa Malick Faye Serigne Département de Géologie Faculté des Sciences et Technique Université Cheikh Anta DIOP Dakar Sénégal

Geochemical and Geostatistical tools were used to assess: 1) the chemical quality and, geochemical processes in crystalline rock aquifers in Sabodala (Eastern Senegal) and its surroundings and 2) the impact of mining activities on their quality. A total of 26 water samples collected at boreholes, dug wells and stream, were analyzed to determine major and trace elements concentration focused on elements that represent more threats on human health. Boxplots define chemical characteristics of water for each aquifer formation compared to surface waters. Geostatistical analysis show two sources of water mineralization with regard to major elements: a first natural source characterized by Ca-Mg-HCO3 water type from boreholes and unpolluted surface water and a second group characterized by polluted water by nitrates with Na-NO3-Cl type mainly observed in upper weathered aquifers. However, considering trace element, geostatistical analysis showed three water groups: water with very low trace element concentrations encountered in boreholes and unpolluted surface waters, and waters with relatively high trace element concentrations such as Al observed in areas affected by gold mining activities and finally, polluted waters by Ni, Co, Mn and Cr observed at Sabodala. Results show that in eastern Senegal well waters are vulnerable and often affected by pollution.

关键词： Geochemistry Geostatistical Crystalline Rock Aquifer Pollution Trace Elements Sabodala Senegal

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

利用土壤切片的数字图像定量评价土壤孔隙变异度和复杂度

引用

土壤学报 2003年第5期40卷 678-682页

作者：李德成 Velde B 张桃林中国科学院南京土壤研究所南京210008 Laboratoire de Géologie

研究结果表明 :利用土壤切片的数字图像 ,以孔隙周长和面积为基础数据 ,可以定量评价小尺度上的孔隙变异度 ,也可以对孔隙复杂度进行研究 ;土壤孔隙在mm尺度上也具有较高的变异度和复杂度 ;粒径 1～ 3mm和粒径 <2cm的重组土壤的孔隙在 2... 详细信息

研究结果表明 :利用土壤切片的数字图像 ,以孔隙周长和面积为基础数据 ,可以定量评价小尺度上的孔隙变异度 ,也可以对孔隙复杂度进行研究 ;土壤孔隙在mm尺度上也具有较高的变异度和复杂度 ;粒径 1～ 3mm和粒径 <2cm的重组土壤的孔隙在 2D空间多呈现网络状 ,而原状土壤的孔隙则多呈不规则的枝状或椭圆状 ;不同处理及不同土壤类型之间在孔隙周长、孔隙度以及孔隙变异度和复杂度方面存在不同程度的差异。

关键词：土壤切片数字图像定量评价土壤孔隙变异度复杂度

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

Experimental study on failure characteristics of single-sided unloading rock under different intermediate principal stress conditions

引用

International Journal of Mining Science and Technology 2023年第3期33卷 275-287页

作者： Chongyan Liu Guangming Zhao Wensong Xu Xiangrui Meng Zhixi Liu Xiang Cheng Gang Lin State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Safe and Effective Coal Mining Ministry of EducationAnhui University of Science and TechnologyHuainan 232001China Post-Doctoral Research Station Huaibei Mining Corporation LimitedHuaibei 235006China Laboratoire de Géologie Ecole Normale SupérieureParis 75005France

Investigation of unloading rock failure under differentσ_(2)facilitates the control mechanism of excavation surrounding *** study focused on single-sided unloading tests of granite specimens under true triaxial *** strength and failure characteristics were studied with micro-camera and acoustic emission(AE)***,the choice of test path and the effect ofσ_(2)on fracture of unloading rock were *** show that the increasedσ_(2)can strengthen the stability of single-sided unloading *** unloading,the rock’s free surface underwent five phases,namely,inoculation,particle ejection,buckling rupture,stable failure,and unstable rockburst ***,atσ_(2)≤30 MPa,the b value shows the following variation tendency:rising,dropping,significant fluctuation,and dropping,with dispersed damages ***σ_(2)≥40 MPa,the tendency shows:a rise,a decrease,a slight fluctuation,and final drop,with concentrated damages *** unloading,AE energy is mainly concentrated in the micro-energy *** the increasedσ_(2),the micro-energy ratio *** contrast,low,medium and large energy ratios drop *** increased tensile fractures and decreased shear fractures indicate that the failure mode of the unloading rock gradually changes from tensile-shear mode to tensile-split *** fractional dimension of the rock fragments first increases and then decreases with an inflection point at 20 *** distribution of SIF on the planes changes asσ_(2)increases,resulting in strengthening and then weakening of the rock bearing capacity.

关键词： Single-sided unloading Acoustic emission True triaxial Intermediate principal stress Stress intensity factor

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

Reassessment of the Resources of a Deep Aquifer System under Physical and Chemical Constraints:The Maastrichtian Aquifer

引用

Journal of Water Resource and Protection 2012年第4期4卷 217-223页

作者： Cheikh Hamidou Kane Moustapha Diene Meissa Fall Baba Sarr Alassane Thiam Département de Géologie FST-UCAD Cheikh Anta Diop University Dakar Senegal ISRA Bambey Senegal Laboratoire de Géologie IFAN Cheikh Anta Diop University Dakar Senegal Laboratoire de Mécanique et Modélisation-UFR Sciences de l’Ingénieur University of Thiès Thiès Senegal

The deep and confined Maastrichtian aquifer contains considerable groundwater resources. It stretches over nearly 200,000 km2, from the northern part of Mauritania to the South of Guinea Bissau where it becomes shallow. The reservoir is composed mainly of coarse sands and sandstone interbedded with some clay units. The aquifer provides 40% of the total drinking water extracted from the different aquifers and nearly 800 wells equally distributed operate only in the top 50 m of the aquifer. Despite the importance of these resources for providing water in the rural and urban areas, the aquifer characteristics are not well defined. The present paper aims to define first the physical and chemical characteristics of the Maastrichtian aquifer. The reserve of the aquifer initially estimated at 350 billion m3, is reassessed using new data providing from cross sections realized as part of our research, through the Water Sectorial Project of the Ministry of Hydraulics. Data from oil wells and geophysical logging are used to investigate the geometry of the aquifer and the position of the fresh/salty water interface. The highest thickness of the aquifer is between 200 to 400 m and salty water is present below the fresh groundwater in the west side of the aquifer. In the Eastern side, potable water lies directly above the basement. The thickness of the aquifer increases from the west to the center, and then decreases towards the shallow basement rock in the South East. The average thickness is 250 m. Chemical data coming from pumping wells indicate high chloride (250 - 1600 mg/l) and fluoride content (1 - 5.5 mg/l). Therefore, the reassessment has to take into account the chemical aspect of the water.

关键词： Maastrichtian Groundwater Deep Aquifer Senegalese-Mauritanian Sedimentary Basin Characteristic Pollution Reassessment

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

A GIS-Agriflux Modeling and AHP Techniques for Groundwater Potential Zones Mapping

引用

Journal of Geographic Information System 2022年第2期14卷 113-133页

作者： Nadia Trabelsi Imen Hentati Ibtissem Triki Moncef Zairi Olivier Banton Laboratoire Eau Energie Environnement Ecole Nationale d’Ingénieurs de Sfax Sfax Tunisia Laboratoire d’Hydrogéologie d’Avignon Avignon France

Groundwater is considered as the main portion of the water supply in arid and semi-arid regions. The Sfax plain area is part of the arid/semi-arid areas of Tunisia that are subject to the impact of climatic and human pressures. Water scarcity in combination with groundwater exploitation is a major concern in this region. Therefore, sustainable management and protection of groundwater resources, it necessary. The delineation of groundwater potential (GP) zones becomes an increasingly important tool for implementing successful management programs. The purpose of the present paper is to assess the potential zone of groundwater resources in the study area. An efficient approach using geographical information system (GIS), hydrological modelling and analytical hierarchy process (AHP) was developed. At first, six groundwater parameters that affect groundwater occurrences are derived from the spatial geodatabase. Those parameters are: Infiltration rate estimated from a GIS linked model, lineament density, drainage density, slope, rainfall and Land use/land cover. Then, the assigned weights of thematic layers based on expert knowledge were normalized by eigenvector technique of AHP. The parameter layers were integrated and modeled using a weighted linear combination (WLC). The resulting map was classified into four categories: very low, low, good, and excellent. The results showed that about 26% of the study area falls under very-low-potential zone, with 30% on low-potential zone, 21% with good potential zone, and 23% falling under excellent zone. The results of the analysis were validated using pumping rate data and curve trend of sensitivity classes theory validation of outcomes indicated a good prediction accuracy. The results of the present study can serve to prepare a comprehensive groundwater development and management plans proving its efficacy in this art of exploratory investigations.

关键词： GIS Groundwater Agriflux Modeling Multi-Criteria Decision Analysis Curve Trend of Sensitivity Classes Theory Sfax

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

Third Conference of the Association of African Women Geoscientists—＂Women, Geosciences and Development＂ El Jadida, Morocco, May 6-11, 2006

引用

Episodes 2006年第4期29卷 293-294页

作者： Ezzoura ERRAMI Chairperson of the Conference Département de Géologie Faculté des Sciences B.P. 20 24 000 El Jadida MOROCCO

A better understanding of the geology and mineral potential of Africa is important in the overall context of social and economic development across the continent. Since 1995 the Association of African Women Geoscientists （AAWG） has existed, holding biennial meetings since 2002, with the aim to encourage women geoscientists to participate in Earth Sciences-related conferences, as well as to inform or become involved on gender issues related to the Earth Sciences.

关键词：地质工作地质行业矿业科学非洲妇女地质家

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

利用数字图像分析土壤表面裂隙的方向分布

引用

土壤与环境 2001年第1期10卷 45-46页

作者：李德成 BRUCE VELDE JEAN-FRANOI DELERUE 张桃林中国科学院南京土壤研究所南京210008 LaboratoireofGéologie

利用二维数字图像方法研究了在土壤干燥过程中表面裂隙方向分布的演化状况。结果表明，随着干燥过程的持续，裂隙的长度、宽度、面积和分数维均趋于增加，但裂隙的方向分布则逐渐趋向均匀。

关键词：方向分布二维数字图像土壤表面裂隙

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

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

在线全文

在线全文

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

在线全文

在线全文

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：