青海洪水河铁矿床矿石特征及加工技术性能

洪水河铁矿是位于青海省东昆仑东段布尔汉布达山北坡的一中型矿床,赋存于中元古界狼牙山组的一套浅变质的钙质绿泥千枚岩加碳酸岩组合中.矿床成因属沉积变质型铁矿床.矿石自然类型主要有磁铁矿、含赤铁矿磁铁矿和赤铁矿等.矿石矿物主要为磁铁矿、赤铁矿、褐铁矿、镜铁矿等,脉石矿物主要是石英,其次是绿泥石、铁白云石和方解石等.矿石中可供...     

东天山寨北山热液脉状铜矿地质特征、成矿时代及矿床成因初探

寨北山铜矿位于东天山阿奇山-雅满苏成矿带的东段。矿体主要赋存于早石炭世玄武安山玢岩中,受断裂构造控制明显。矿石以脉状、浸染状构造为主,矿石矿物主要为黄铜矿,黄铁矿较少。围岩蚀变较弱,分带性不明显。获得矿区黄铁矿Re-Os同位素模式年龄为337. 9±5. 7 Ma,表明该矿床形成于早石炭世。矿区硫化物硫同位素δ~(34)S值介于-1. 4‰～-7. 2‰之间,接近于幔源硫值;矿石石英中δD值为-105. 6‰～-96. 4‰,δ~(18)O值为0. 3‰～3. 2‰,反映成矿流体主要来自岩浆。综合研究认为寨北山铜矿可能为一火山-次火山热液型矿床。     

新疆东天山红云滩铁矿床磁铁矿标型和硫同位素特征及其意义

红云滩铁矿床是新疆东天山阿奇山-雅满苏构造带中一个富铁矿床,矿体赋存于石炭系雅满苏组安山质凝灰岩和晶屑凝灰岩中,呈层状、似层状或透镜状产出,矿区分为东西两个矿段。矿石以块状和浸染状为主,脉状次之,局部有条带状和网脉状。矿石矿物主要为磁铁矿,脉石矿物组合为绿泥石、石榴石、透闪石、阳起石、绿帘石和石英等。根据野外及镜下观察,可将红云滩矿床分为两期3个成矿阶段,按阶段分别为(1)火山喷溢成矿阶段,(2)矽卡岩+磁铁矿阶段,(3)石英-硫化物+磁铁矿阶段,磁铁矿主要形成于矽卡岩+磁铁矿阶段。磁铁矿的电子探针数据显示FeO含量变化较大,在88. 80%～93. 19%之间,具有低的TiO_2含量(0～0. 21%),较高的SiO_2(0～1. 77%)、MgO(0～1. 19%)、CaO(0～1. 51%)、Al_2O_3(0～0. 94%)含量,显示出热液型磁铁矿特征。TiO_2-Al_2O_3-(MgO+MnO)、TiO_2-Al_2O_3-MgO和(Ca+Al+Mn) vs (Ti+V)图解表明,磁铁矿形成与火山沉积和火山热液活动有密切关系。红云滩铁矿床黄铁矿硫同位素变化范围较大,δ~(34)S值在-3. 8‰～4. 7‰之间,指示成矿物质主要来自深部岩浆系统。红云滩铁矿床的形成在时间上和空间上均与海底火山活动密切相关,结合矿床地质特征,认为红云滩铁矿为火山喷溢-火山热液型矿床。     

冀东湾杖子铁矿床地质特征、成矿规律及成因探讨

冀东地区是中国重要的沉积变质型铁矿资源地之一,随着开发程度的提高,当前面临着后备资源不足的问题,加强区内铁矿成矿规律研究,有助于寻找新的铁矿资源,进而缓解冀东地区铁矿后备资源紧张的局面。湾杖子铁矿床位于冀东地区的北东部,是一处中型铁矿床,矿体赋存于新太古界遵化岩群湾杖子岩组和三门店岩组变质岩中。本文在分析矿区以往勘查资料和笔者在本区勘查实践的基础上,总结了湾杖子铁矿床的成矿地质背景、矿床地质以及矿石特征,结合区域上前人研究成果,对该矿床的成矿规律和成因进行了初步研究。研究表明：湾杖子铁矿床为一典型的沉积变质型铁矿床,矿床由密集群带状分布的多条铁矿体组成,矿体形态以透镜状为主,沿走向和倾向具有明显的膨缩、尖灭再现现象。矿石主要由磁铁矿和石英组成,具有半自形—他形粒状变晶结构,条纹—条带状构造,矿石类型为需选弱磁性铁矿石。矿体的空间分布主要受地层控制,矿体总体有向南西倾伏的迹象,推测可能受控于枢纽向南西倾伏的向斜构造。成矿物质主要来自海底火山活动高温热液,沉积环境物理化学条件的改变导致硅质、铁质元素依次沉淀,形成原始条带状硅铁质建造,后经多次构造作用和变质改造形成条纹状、条带状铁矿石。研究...     

安徽宁芜盆地杨庄玢岩型铁矿地质特征及找矿方向

安徽省杨庄铁矿是近年来在钟姑山矿田新发现的又一大型铁矿床,位于宁芜盆地南段钟姑山复背斜的次级褶皱向阳向斜构造的北转折端,矿体主要赋存于徐家山组与闪长(玢)岩的内外接触带、三叠系徐家山组地层中及闪长(玢)岩内部,整体走向NW,倾向SW,局部倾向SE,倾角变化较大,总体呈似层状、层状、透镜状产出,局部具分支复合、膨大收缩,尖灭再现等特征,矿石以磁铁矿为主,次为(假象)赤铁矿矿石,矿石结构以他形-半自形微细粒结构为主,矿石构造以浸染状-稠密浸染状构造为主,矿床成因应属气化-热液交代为主的充填-接触交代型铁矿床,明显有别于已有的凤凰山(白象山)式、姑山式铁矿床,应为新亚式"杨庄式玢岩铁矿"。该新亚式的提出,丰富了"玢岩铁矿"模式。     

北祁连西段小沙龙铁矿床矿石特征及矿床成因

从矿石研究入手,文章论述了北祁连西段小沙龙铁矿床的矿石类型、组构、成分等特征.该铁矿石主要为泥钙质板岩型,包括磁铁矿矿石、菱铁矿矿石、赤铁矿磁铁矿矿石、黄铁矿化磁铁矿矿石、磁铁矿菱铁矿矿石等5种自然类型,金属矿物主要为磁铁矿、菱铁矿、赤铁矿,次为黄铁矿、褐铁矿,矿石全铁含量较低,磁铁矿颗粒较细,这些特点与火山沉积变质型铁矿床一致.     

山东洼子铁矿地质特征及成因探讨

洼子铁矿位于山东省莱州市西南部莱州—昌邑铁成矿带上,古元古界粉子山群小宋组中下部富铁岩系控制了铁矿体的分布,矿体形态总体呈似层状,沿倾向呈透镜体状,沿走向呈舒缓波状展布。矿石矿物以磁铁矿为主,少量黄铁矿。铁矿体底部的厚层大理岩是间接找矿标志,磁异常是重要的找矿标志。其成因为与区域变质作用密切相关的变质沉积铁矿床。     

内蒙古嘎仙镍钴矿区物探找矿方法技术组合及应用

嘎仙镍钴矿地处西伯利亚地台与中朝准地台过渡地带,位于内蒙—大兴安岭褶皱系大兴安岭优地槽褶皱带,属岩浆熔离—热液改造型硫化物镍矿床.该矿床类型特征与常见的铜镍硫化物矿床不同,镍品位低、贫铜,镍钴矿(化)体赋存辉石橄榄岩中.金属矿物主要由黄铁矿、镍黄铁矿和磁铁矿等组成,其中镍黄铁矿与黄铁矿紧密共生,成不规则颗粒状镶嵌于黄铁矿中;而磁铁矿—般形成较晚,多见于镍黄铁矿中,呈网脉状产出.磁黄铁矿、镍黄铁矿呈浸染状、细脉状、细脉浸染状,局部斑块状、脉状,矿产于辉石橄榄岩中.通过对该区开展的地球物理工作,不仅对镍矿(化)体的空间分布特征及矿化富集规律有了很好的认识,而且总结出了该区找矿的最佳技术方法组合,即大功率单极—偶极测深装置激发极化法与高精度磁法的结合.     

内蒙古长汉卜罗铅锌银矿床地质特征及成因探讨

长汉卜罗铅锌银矿床位于华北克拉通北缘。矿体受东西、北东向断裂控制,主要以脉状、透镜状赋存于石英斑岩、花岗闪长岩、安山岩内及不同岩性接触带。金属矿物以方铅矿、闪锌矿、黄铁矿为主,其次为黄铜矿、毒砂、白铁矿、黝铜矿、银黝铜矿等。围岩蚀变主要在矿脉两侧发育,包括黄铁矿化、绢云母化、硅化、绿泥石化、绿帘石化、碳酸盐化等。成矿过程可划分为3个阶段:石英—黄铁矿阶段(Ⅰ阶段)、多金属硫化物阶段(Ⅱ阶段)和石英—碳酸盐阶段(Ⅲ阶段)。矿床形成可能与近同期的火山—次火山岩浆作用相关,为次火山热液型矿床。     

山东莱州—安丘地区沉积变质型铁矿床地质地球物理特征及成矿规律

莱州—安丘地区是山东省重要的铁矿资源分布区,铁矿主要成因类型为沉积变质型。区内沉积变质型铁矿赋存于粉子山群小宋组,矿体呈层状、似层状及透镜状沿北东向断续分布,矿石主要类型为磁铁变粒岩型和磁铁石英岩型,矿床地球物理场特征表现为北东向重力梯级带和条带状高磁异常。文章在分析研究沉积变质型铁矿床地质、地球物理特征的基础上,总结了该类型铁矿的成矿规律和找矿标志,以期为该区同类型铁矿勘查提供参考。     

浅析高速公路工程招投标中的最低评标价法

结合目前高速公路施工项目招投标活动的实际情况,阐述了最低评标价法的概念,归纳了其优点及存在问题,对完善最低评标价法提出几点策略,以期促进招标投标市场更加规范有序。     

Place-Making in Megaprojects in Melbourne

This article analyses state-led place-making practices in Melbourne. The two levels of government that influence planning in Melbourne make much of the city as ‘culturally vibrant’ and ‘creative’, and have incorporated creative city-inspired place-making principles into many layers of the planning system. An examination of the development of two mixed-use megaprojects in central Melbourne reveals however that ideals of culturally engaging public places, and indeed of creative landscapes for middle-class consumption, wither in the face of more basic imperatives for economic development. In these case studies the ‘creative city’, no matter how the idea is interpreted, has little traction either as a set of inclusive place-making principles or as a gentrification strategy. The article concludes that the creative city-inspired place-making objectives in the planning system at both state and local levels are ambiguous in their overall intents and completely unsupported by statutory controls. Such place-making objectives as are realised are the compromised results of the interplay of uncoordinated decisions, delivered at the pleasure of the developer.     

Pathogens in septage in Vietnam

Septage is widely acknowledged as a major source of infectious pathogens while disposal of septage, and the operation and maintenance of septic tanks, is not regulated in many developing countries. Twenty untreated septage and septage sludge samples were taken from Can Tho City, Vietnam to examine their pathogen content, and indicator micro-organisms. Escherichia coli and Enterococcus spp. were detected in all samples, regardless of sludge storage time. Phages were detected in 80% of samples. Salmonella spp. were detected in 70% of the untreated septage and 60% of septage sludge samples. Concentrations of phages and bacteria tested in septage sludge after many years of tank storage were much higher than the expected levels. Helminth ova were present in 95% of untreated septage samples with an average of 450 ova l^− 1, and were detected in all septage sludge samples with an average of 16,000 ova l^− 1. Twelve varieties of helminth ova were identified. More helminth ova varieties in higher concentrations were found in septage than those reported from stool samples. The varieties' frequency ranged from 10% to 50% and Ascaris lumbricoides predominated. Results show that pathogens and indicator micro-organisms, especially helminth ova, accumulate in sludge. Thus helminth ova should be considered when septage sludge is treated and used for agriculture. Proper health protection measures must be applied for people handling septage.     

在市场中实践在实践中学习在学习中进步--工程公司市场化进程的回顾与展望

近两年来，工程公司在提高市场竞争意识、推动市场化进程中做了大量工作，其中坚持走出去的方针是我们自我加压、推行加快市场化步伐的一个重要战略步骤。     

新时期广东城市化的新特点

新时期广东城市化出现以下特点:知识源导向、城市由单体向群体化发展、产业集群推动、政府主导自上而下的集约化发展、城镇化向城市化转变、由重“数量”发展向重“质量”发展的转变。     

新形势下高校强化基建财务管理的探讨

在市场条件下高校基建财务人员在加强日常财务管理的同时,必须树立起高度的工作责任心,抓好事前监督、事中监督、事后监督三个环节,全面理解、贯彻执行《高等学校财务制度》,管好用好各项基本建设资金,提高基建财务管理水平,更好地完成高校各项基建任务,以有限的投资,最快的建设速度,获得最大的投资效益。     

2005年北京办公物业市场七大趋势

趋势一:CBD区域写字楼集中放量从各区域规划方案上看,CBD区域多数项目在03～04年处于项目的报批手续及拆阶段,预计2005年正式推向市场,因此2005年CBD区域将成为北京市场供应集中的域,区域即将供应的项目有北京财富中心(二期)、金地国际花园、万达广场、SOHO尚都、万通中心、世纪财富中心、怡禾国际中心、光华国际等。除去未知项目,2005CBD写字楼办公面积的供应量为60万平方米左右。中关村区域经过一段时间的集中供后开始逐步放缓,2005年供应的体量相对较大的项目有中关村金融中心、新中关。金街区域可能开盘的项目只有2个:英蓝国际中…     

浅谈我国工程项目建设成本控制存在的问题

结合目前我国施工企业工程项目成本管理现状,对工程项目成本管理过程中存在的问题进行了较详细的分析,并提出了一些解决问题的办法,以做好项目成本控制工作,进而增强企业经济实力。     

Variation in property taxation in Tulsa

Conclusions It may be reasonably concluded from this study that the range of variation in these ratios of assessed to actual value are of a reasonable size for the great majority of cases. The frequency distribution of these sample ratios was not normal, however, as was assumed a process of this type would produce. On the other hand, the failure of the regression analysis to identify any significant variables which would explain these variations would tend to re-enforce the assumption that the fluctuations were indeed of a random nature.To sum it up in one paragraph, aside from a few extreme cases, the assessing process appears to give estimates which are more consistent than would be expected under the assumption that any errors would be of a random nature, but the regression analysis was unable to isolate any particular socioeconomic characteristics which would explain the variation which was present.Financial support for this research project was furnished by the University of Tulsa.