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1.
华北地台东部晋冀鲁京津地区早奥陶世岩相古地理   总被引:7,自引:3,他引:7  
冯增昭 《沉积学报》1986,4(4):28-40
一、前言早奥陶世时期的“华北地台”是一个十分广阔的碳酸盐台地,西至贺兰山以西,南至祁连山、秦岭、伏牛山、大别山,东至渤海和东海,北至阴山以北,包括陕、甘、宁、蒙、晋、冀、鲁、辽、吉、豫、皖、苏、京、津等十四个省、市、自治区的全部或部分地区,是我国最大的地台之一。本文涉及的范围乃华北地台东部的腹地,即西至黄河,东至海,南至陇海路,北至内蒙;乃晋、冀、鲁、京、津的全部或大部地区,也包括豫北、苏北、辽西部分地区。  相似文献   

2.
马鞍山钢铁股份有限公司设计研究院隶属于马鞍山钢铁股份有限公司,是钢铁行业甲级设计院。总占地面积8000平方米,总建筑面积近7000平方米。该院历史悠久,技术力量雄厚,专业配套,技术装备先进齐全。现有职工500人,设置科室27个。共设有烧结、炼铁、机运、炼钢、轧钢、工业炉、设备、制造、总图、电力、电控、计器、通讯、计算机、热力、燃气、通风、环保、给排水、土建、建筑、结构、  相似文献   

3.
我们伟大的社会主义祖国,幅员广大,海域辽阔,蕴藏着丰富的矿产资源。新中国成立50年来,我国广大地质工作者,在前人工作的基础上,通过大规模区域地质、区域地球物理调查和区域地球化学扫面,以及矿产普查勘探和相应的地质科学研究,在全国范围内,累计发现各类矿产168种,矿产地和矿化点20多万处。探明有储量的矿产151种,矿区16000多处。煤、钨、锡、锑、钼、钒、钛、铅、锌、稀土、石墨、滑石、重晶石、萤石、菱镁矿、石膏、膨润土、岩盐、硅灰石、硅藻土等20多种矿产的探  相似文献   

4.
新疆境内的天山地区,地层发育齐全,沉积建造多样,岩浆活动频繁,构造类型复杂,矿产种类繁多.矿产种类比较齐全,燃料能源、黑色金属、有色金属、稀有金属、稀土元素、化工、建材和其他非金属等均有发现,特别是新疆的锰、钛、钒、钨、钼、铝、汞、钠硝石、磷、菱镁矿、食盐和芒硝等几乎全产于天山,煤、铁、铝、锌、重晶石、石灰岩和粘土矿等,也都产于天山.天山矿产具有矿种多、分布广、类型复杂,配套基本齐全的特点,是目前新疆矿业开采最重要的生产基地,对本区建设起着十分重要的作用.本文是在综合大量地质普查和矿区勘探资料的基础上,试图对天山地区矿产形成的基本特点,矿床成因分类和主要分布规律等进行初步分析和探讨,不足和错误之处,请读者批评指正.  相似文献   

5.
前言明清以来,我国产铜中心,渐移西南,尤以川西、康东、滇北、地理上极接近的区域为最著。北起四川彭县白水河,中经川西的洪雅、峨眉、康东的天全、宝兴、荣经、越巂,以迄西康东南的会理,滇北的东川、巧家、宣威,滇中的路南、易门,滇西的保山、永胜等县,旧矿甚多,蔚为我国西南最重要的产铜地  相似文献   

6.
以牦牛坪稀土矿区下游水系沉积物剖面为研究对象,探讨了矿山开发对河流沉积环境演化的影响.研究结果显示,水系沉积物剖面中的元素含量变化可分为0~10 cm、10 ~ 30 cm、30 ~ 40 cm、40 cm以下4个沉积时期.应用放射性核素21opb确定沉积年代,得出1910年至今,河流的平均沉积速率大约为0.45 cm/a.根据沉积速率变化趋势将沉积分为4个阶段:1910 ~ 1940年,沉积厚度大约为5 cm,平均沉积速率为0.168 cm/a,该阶段K、Na、U、S、Mo、Mn、Pb、F含量逐渐降低;1940 ~1990年,沉积厚度大约为22 cm,平均沉积速率为0.44 cm/a,浅层的12 cm呈现低K、Na、U、S、Mo、Mn、Pb、F,相对高pH、N、P、有机质的特征,深层的10 cm呈现相对高K、Na、U、S、Mo、Mn、Pb、F的特征;1990 ~1999年,沉积厚度约为8 cm,平均沉积速率为0.889 cm/a,该阶段呈现低K、Na、U、S、Mo、Mn、Pb、F,相对高pH、N、P、有机质的特征;1999年至今,沉积厚度大约为10 cm,平均沉积速率为0.909 cm/a,该阶段呈现低pH、N、P、有机质,高K、Na、U、S、Mo、Mn、Pb、F的特征.  相似文献   

7.
赣西北下寒武统黑色岩系,是一套重要的铀等金属的含矿岩系,其中观音堂组碳硅泥岩是典型的黑色岩石类型。运用地球化学方法,对这套灰黑色泥质岩的元素地球化学及古环境演变特征进行了研究。研究结果表明:该碳硅泥岩黏土类矿物含量55%~59%,SiO_2,Al_2O_3,Fe_2O_3,K_2O,MgO平均含量分别为69.47%,11.39%,3.32%,2.76%,1.57%;化学成分表现为高硅低铝低钾低镁特征,有机碳平均含量5.82%,属富碳黑色岩系。对比中国东部泥质岩,其Ni、V、U、Ba、Cd、In、Tl、Se、W、Mo、Cu、Zn、Au、Ag、As、Sb等元素有相对富集的特点。从碳硅泥岩层的上部到下部,SiO_2、Na_2O、Ni、Mo含量逐渐增高,Al_2O_3、K_2O、TiO_2、H_2O^-、LOI、Cr、Th、Ba、Ga、Li、Be、Rb、Sc、Sn、Bi、Cu、Pb、Zn、Ag、REE则显示逐渐降低趋势。主量或微量元素的判别参数或图解显示,碳硅泥岩的物源以陆源碎屑岩为主,是在一个沉积速率较小、且较稳定的深水还原环境下沉积的,从早期到晚期,物源区呈现风化作用逐渐增强、气候环境越来越湿润、盆地水质越来越淡化的趋势。  相似文献   

8.
奇石,又称观赏石,雅石,是指不事雕琢,具有自然美感的石头。包括奇特的化石,矿物晶体和岩石等。奇石具有独特的形态、色泽、质地、纹理。奇石具有观赏、收藏及科研价值。古人云:“山无石不奇,水无石不清,园无石不秀,室无石不雅。赏石清心,赏石怡人,赏石益智,赏石陶情,赏石长寿。”观赏奇石,要讲究瘦、漏、透、皱、清、丑、顽、拙、奇、秀、  相似文献   

9.
郭福祥 《地质科学》1986,(2):161-169
滇西兰坪思茅地区,中、新生代红层发育,北起德钦一带,经维西、兰坪、云龙、漾濞、南涧、景东、镇源、景谷、普洱、思茅、江城,延至勐腊地区,东以苍山、哀牢山为界,向西展布于澜沧江沿岸。早侏罗纪至中白垩世,长期相对沉降,形成北北西—南南东向拉长的大型盆地堆积,分布广,几乎遍及全区,近盆地中心,连续沉积,形成了巨厚的红色碎屑岩群。时而有膏盐堆积,但远不如后来的含盐组重要,本文略之。  相似文献   

10.
一、强管理,重质量,创精品,上水平——以质量求生存,以改革求发展 我院成立于1953年,是集工程勘察、设计、科研于一体的大型甲级设计院。现持有国家公路勘察、设计、测绘、环保、技术咨询及施工监理等甲级证书,主要承担公路、桥梁、隧道、交通工程、环境工程的勘察、设计、科研、施工监理、技术咨询等多项业务。 建院47年,尤其是近十年来,我院坚持“质量为本、科技领先、管理科学、服务优质”的工作指导方针,真抓实干,当好公路建设的先行官,确保了国家  相似文献   

11.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

12.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

13.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

14.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

15.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

16.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.  相似文献   

17.
18.
《Applied Geochemistry》2001,16(2):137-159
Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km2 area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).  相似文献   

19.
We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al2O3-SiO2 ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses.  相似文献   

20.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

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