浅析贵州二叠系锰矿与峨眉山玄武岩之关系

贵州遵义-水城地区中二叠纪茅口组第二段顶部产出的原生碳酸锰和氧化锰矿床,为贵州二叠系锰矿主要矿床。贵州中西部有大量的峨眉山玄武岩分布。本文就贵州二叠系锰矿与峨眉山玄武岩之关系进行探讨。     

贵州及邻区二叠系锰矿地质特征及成矿作用探讨

本文在系统收集和分析了近年来贵州锰矿资源评价工作及以往锰矿工作资料的基础上,获得了对贵州及邻区二叠系锰矿更深入系统的认识。主要成果为：认为该区中二叠世茅口期含锰岩系可大致对比,可沿用遵义锰矿产出地区所使用的名称——中二叠统茅口组白泥塘层（P2m^b）;水城纳雍锰矿与宣威格学锰矿特征及成矿机制十分相似,均为第四纪氧化富集成矿,矿床类型属于风化矿床类的锰帽型锰矿床亚类,矿质来源于原始沉积的含锰岩系——白泥塘层,而白泥塘层的锰质来源于中二叠世茅口期峨眉山玄武岩喷发;将贵州及邻区二叠系各类型锰矿床的特征及含锰岩系、物质来源、成矿作用等方面作了有机联系和系统分析,并建立了统一的成矿模式。     

云南省香格里拉县九龙峨眉山玄武岩岩石特征及构造背景

广泛分布于中国西南云、贵、川三省的二叠系峨眉山玄武岩(赵亚曾,1929)一直受到国内外关注,本文旨在对云南省香格里拉县九龙地区分布的峨眉山玄武岩的岩石喷发序列、岩石组合及岩石化学特征,岩石构造背景做初步研究,并将其特征简单与四川省境内分布的峨眉山玄武岩做对比。     

贵州威宁县黄泥坡峨眉山玄武岩铜矿产出特征及成矿规律浅析

通过对贵州威宁县黄泥坡峨眉山玄武岩铜矿产出地质特征、成矿地质背景、成矿规律的研究,发现主要赋矿地层为峨眉山玄武岩组第二、三段的多孔玄武岩,且成矿与构造关系密切。总结出岩性、围岩蚀变、矿物等找矿标志,为在该地区找玄武岩铜矿提供了依据。     

滇东北会泽地区玄武岩岩石类型及地球化学特征

滇东北会泽地区广泛分布玄武岩,主要岩石类型为溢流相致密状、杏仁状、斑状玄武岩,通过对滇东北会泽地区二叠系峨眉山玄武岩岩相岩石类型调查及地球化学特征分析研究,根据地球化学特征进行玄武岩系列划分,岩石成因分析,构造环境判别。     

滇东北会泽地区玄武岩岩石类型及地球化学特征

滇东北会泽地区广泛分布玄武岩,主要岩石类型为溢流相致密状、杏仁状、斑状玄武岩,通过对滇东北会泽地区二叠系峨眉山玄武岩岩相岩石类型调查及地球化学特征分析研究,根据地球化学特征进行玄武岩系列划分,岩石成因分析,构造环境判别。     

滇中中—上二叠统峨眉山组关键金属勘查新线索及地质意义

通过1∶5万区域地质调查及典型剖面研究,在滇中禄劝地区二叠系峨眉山组顶部识别出一套厚约20~50 m不等的Nb、Co、Ga、Zr及REE超常富集层。富集层主要岩性为灰紫色泥岩、凝灰质泥岩、凝灰岩,局部夹杏仁状玄武岩。通过对禄劝万鲁布、撒角海一带的富集层刻槽分析显示,Nb2O5含量在82.4×10-6~120.1×10-6,平均值为100.3×10-6,大于风化壳型矿床一般工业指标80×10-6;Ga 含量28. 8×10-6~35.6×10-6,平均值为32.1×10-6,高于现行的Ga矿资源工业指标要求30×10-6;REE含量在360×10-6~510×10-6,平均值为440.6×10-6,接近风化壳型矿床一般工业指标500×10-6;并呈现出泥岩凝灰质泥岩凝灰岩关键金属含量依次升高,与火山灰含量呈正相关的特征,峨眉山玄武岩的风化作用可能造成了关键金属的富集;同时富集层中伴有Co、Zr、Li等关键金属矿化现象;由此,二叠系峨眉山组红顶层是一个关键金属的富集层,鉴于滇中地区二叠系峨眉山组分布范围较广,是一个极具Nb、Ga、Co、Zr及REE等多种关键金属找矿前景的地区,值得找矿工作者关注。峨眉山组各段玄武岩间富集关键金属的火山碎屑岩－沉积岩夹层（10~120 cm）、沥青杏仁体的发现,佐证了峨眉山玄武岩是地幔柱幕式喷发,为峨眉山玄武岩地幔柱演化、喷发时限及其与二叠纪生物灭绝的关系、寻找常规油气提供了新的研究方向及资料。     

遵义地区二叠系锰矿成矿物质来源及成矿模式探讨

黔北遵义地区二叠系锰矿资源丰富,是贵州省内仅次于黔东北地区的重要锰矿富集区及生产基地。矿床地质特征研究表明,遵义锰矿主要含矿层位为中二叠统茅口组第三段,矿石以原生锰矿为主,主要由碳酸盐锰矿组成,属低磷、高铁、高硫的酸性矿石。成矿地质背景、岩浆活动、矿物组合特征以及元素地球化学性质的综合分析表明,遵义锰矿成矿物质与峨眉山玄武岩有关,锰矿主要形成于海底火山喷发引起的热液(水)喷流沉积。     

贵州水城-纳雍地区峨眉山玄武岩风化壳离子吸附型稀土矿床地质特征及资源潜力

通过对贵州水城—纳雍地区峨眉山玄武岩风化壳离子吸附型稀土矿床的风化壳结构、矿体垂向变化特征的综合研究,总结了矿床特征、风化壳特征、区域成矿条件。风化壳中全风化层是稀土矿富集最好的层位; (La/Yb)N、ΣLREE/ΣHREE比值较高,属于强轻稀土富集类型。严格受母岩、地形、气候、地层、构造等因素共同作用。稀土矿床具备分布面广、埋藏浅、厚度大、品位高等地质特征。可以指导贵州西部地区寻找同类型大型稀土矿产地。     

基于GIS的攀西地区铂族元素成矿地质条件初步分析

攀西地区以良好的铂族元素(PGE)成矿地质背景，而成为我国铂族元素找矿热点地区之一。本文在建立攀西地区铂族元素矿床地质概念模型的基础上，用地理信息系统(GIS)分析了该地区的铂族元素成矿地质条件，包括地质构造、峨眉山玄武岩、基性一超基性岩和铂族元素地球化学异常特征。指出研究区的深大断裂对铂族元素的富集表现出很好的控制作用，峨眉山玄武岩为铂族元素的矿源层之一，岩浆岩为铂族元素的富集提供了成矿物质及成矿能量。     

Définition d'une limite multicritère ; stratigraphie du passage Campanien–Maastrichtien du site géologique de Tercis (Landes,SW France)Definition of a multi-criteria boundary; stratigraphy of the Campanian–Maastrichtian interval of the geological site at Tercis (Landes,SW France)

Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ₁ roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).     

HYDROGEOLOGY

正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level     

METAMORPHIC PETROLOGY

正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),     

SERIALS

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GEOPHYSICAL EXPLORATION

正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-     

PETROLEUM GEOLOGY

正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)     

GEOCHEMISTRY

正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861     

ENGINEERING GEOLOGY

正20141768 An Shaopeng(Institute of Rock and Soil Mechannics,Chinese Academy of Sciences,Wuhan 430071,China);Wei Lide Experimental Study on Mechanical Behavior of Xigeda Formation Siltstone and Structure Interface(Journal of Engineering Geology,ISSN1004-9665,CN11-3249/P,21(5),2013,p.702-708,9illus.,1 table,16 refs.)