甘肃北山地区红山铁矿床成因及成矿机制

甘肃北山地区红山铁矿床为赋存于元古界青白口系顶部的沉积变质型铁矿床,其铁矿石主要类型为磁铁矿,少量为赤铁矿、镜铁矿。矿石储量可达亿吨,经野外调研和室内综合研究,本矿床形成于裂陷海盆中,与多处含铁的热卤水喷流柱上涌有关,属于"Sedex"型铁矿类型。     

大红山铁铜矿床的成矿与找矿问题

大红山矿区由一个大型富铁矿和一个大型铜矿组成.两个矿床均产于前震旦纪优地槽的一套变质火山岩系中.含矿系属于细碧-角斑岩、绿色片岩及混杂大理岩组合建造.矿床的生成与海底火山喷发-沉积作用直接有关.探讨海底火山喷发-沉积作用及其韵律特征与成矿的关系,对指导类似地质条件地区的找矿工作,会有一定的现实意义.一海底火山喷发沉积韵律与成矿大红山铁铜矿床是海底火山喷发-沉积作用的不同阶段、不同环境和不同条件下之     

红山铁矿床成因及成矿机制探讨

对红山铁矿5个矿区矿石矿物组分及组构特征、矿层及围岩蚀变与沉积环境的分析表明,各矿区的铁矿体均赋存于青白口系第四岩组上部呈层状产出,不同矿区的铁矿层无上下层位之分,含铁岩系受背斜构造的控制.铁矿床属海相沉积变质成因.     

新平大红山铜铁矿床控矿因素及成因分析

大红山铜铁矿床是我国著名的大型铁铜矿床之一。对成矿地质背景、矿床地质、矿体特征等综合研究,分析矿床控矿因素,提出矿床成因为火山-喷发沉积变质型,建立了成矿模式。     

西昆仑帕米尔式铁矿床膏铁建造成因探讨——以老并铁矿为例

产于塔什库尔干陆块下古生界含铁岩系的西昆仑帕米尔式铁矿床具有独特的膏铁建造特征。老并矿区具有明显的6个沉积铁矿化层,由下往上构成"粗碎屑岩-中基性火山岩夹层-磁铁矿层-含铁膏岩层-细碎屑岩"退积正粒序组合的沉积层,与火山活动关系密切,成矿物质主要来源于火山物质。在海底火山喷发过程中,深部火山岩浆与海水硫酸盐矿物发生混染作用,含铁热水溶液与膏岩层作用。随着温度、压力、pH值等环境条件的转变,先后结晶出硬石膏、磁铁矿、黄铁矿并沉积形成不同矿物组合的膏铁建造。     

新疆西昆仑塔什库尔干地区“帕米尔式”磁铁矿床地质特征及成因分析

通过对"帕米尔式"铁矿床的野外地质调查及成矿地质背景、矿床地质特征、矿床地球化学特征、成矿机制和找矿标志进行研究分析,发现该类型铁矿床的铁矿体矿体主要呈层状、似层状、透镜状赋存于下古生界马尔洋组的含铁岩系中,与围岩呈整合接触、互层产出,原生沉积层理清晰,沉积构造特征明显,矿石局部具热液、变质作用改造特征;并具有较为独特的膏铁建造特征,同时稀土元素分析结果表明,"帕米尔式"铁矿床具有海洋化学沉积特征,且与海底中基型火山活动密切相关,为一种新型的铁矿床。     

西昆仑甜水海地块大红柳滩铁矿床成因浅析及找矿意义

位于西昆仑甜水海地块东段的大红柳滩赤铁矿是近几年发现的大型铁矿床,产于震旦纪甜水海岩群滨浅海相浅变质碎屑岩-碳酸盐岩中,赋矿岩性主要为含铁白云质大理岩、白云母石英片岩和硬绿泥石白云母石英片岩。通过矿体形态特征、矿物组合和矿石结构构造分析,认为该时期存在缺氧富铁洋盆或者深水盆地,矿床的形成经历了铁质沉积和变质改造两个阶段,属于新元古代沉积变质成因条带状硅铁建造矿床(BIF),找矿潜力巨大。该矿床是继塔什库尔干县一带发现了多个与火山岩建造密切相关的大型规模Algoma型BIF之后的重大找矿突破,也是西昆仑地区首次发现该类型矿床。深入开展该矿床的地质特征及勘探工作,能够指导西昆仑铁矿的下一步找矿方向,推进新疆地区条带状含铁建造(BIF)研究和西昆仑构造格局演化的认识。     

滇西惠民式铁矿找矿模型及预测

惠民铁矿产于双江陆缘弧带中元古代惠民岩组中部多旋回含铜铁火山-沉积建造中。每个小旋回底部由火山岩始,顶部至铁矿层终,构成明显的火山喷发-沉积韵律,铁矿层的大小、分叉、尖灭等,与火山岩的多寡、厚薄直接有关,受控于火山岩活动及其中心。将其厘定为云南省云县-澜沧一带区域性的中元古代海相火山-沉积型铁矿典型矿床-惠民式铁矿,并将与之成矿条件类似的双江-澜沧地区中元古代火山岩盆地作为惠民式铁矿的预测工作区,以MRAS定位定量方法,基于GIS矿产资源评价系统进行矿产预测,优选最小预测靶区13个,估算铁矿石资源量75亿吨,做为今后寻找与勘查该类型矿床的依据。     

志留纪昆仑山地区构造古地理环境及其成矿意义

青藏高原北部基础地质调查与研究工作中,在昆仑山地区测得志留纪(S),奥陶纪—志留纪(O-S)剖面39条,剖面厚度从169m到8260m不等,地层的上下接触关系多为断层和角度不整合。从沉积环境、物质组成等方面,反映出昆仑地区从西向东古地理环境为滨浅海-深海-滨浅海-深海的分布特征。西昆仑温泉沟群(S1W)在英吉莎县西,以砂岩、板岩为主,沉积环境为浅海陆棚;在麻扎一带,主要为砂岩、粉砂岩、板岩及硅质岩等,麻扎附近的石英片岩、砂板岩及灰岩中,含拉斑玄武岩,为活动大陆边缘环境下,深海相(俯冲带海沟沉积环境,麻扎一带),斜坡相浊积岩沉积(麻扎东、西一带),在麻扎一带叠复厚度8260m,向北西、南东方向变薄;东昆仑在木孜塔格峰北,该群为一套深海-半深海复理石沉积,由灰色、浅灰色浅变质各种岩屑砂岩、粉砂岩、泥岩组成。中晚志留世达坂沟群(S2-3D)在西昆仑为半深海到滨浅海沉积环境,在东昆仑沉积一套碳酸盐岩夹碎屑岩地层,以浅海环境为主。在若羌南的白干湖组(S1b)发育深海浮游生物——笔石,为深海相浊积岩,从下到上浊积扇向海推进,水体逐渐变深,属拉张环境下的深海弧后盆地沉积环境。在格尔木西南志留系赛什腾组(Ss)自下而上由大陆斜坡至陆隆和深海沉积到浅海的沉积环境演化,具有非扇大陆斜坡沉积类型,以远源浊积岩、半远洋沉积为特征,代表古海盆收缩到残留海盆阶段的沉积。布咯达坂峰东,加里东晚期(S3)同碰撞型二长花岗岩体锆石的LA-ICP-MSU-Pb年龄(421±3)Ma、(423±16)Ma。在格尔木东南的纳赤台群(OSN)超镁铁岩-辉绿岩墙-玄武岩-深水硅质岩构成早古生代的洋壳组合,具有蛇绿岩套特征。基性变玄武岩显示为洋中脊或洋岛环境。硅质岩的地球化学指标也显示为洋中脊或大洋盆地的远洋深水环境,超镁铁岩是古洋壳残片的地幔岩部分,变碎屑岩属大陆斜坡相沉积,碳酸盐岩具近岸沉积特点。格尔木东南纳赤台群大洋中脊拉斑玄武岩(MORB)型,锆石SHRIMP206Pb/238U年龄的加权平均值为(419±5)Ma,为S4。总体上,志留纪昆仑地区应是加里东运动之后在逐渐消失的残留洋,表现出复杂的多岛洋盆体系。这一构造古地理环境的确定,为该地区已经发现的矿床形成机制的研究和下一步的找矿工作提供了重要的依据。     

云南大红山铁铜矿Ⅱ_1矿组地质特征

大红山铁铜矿区位于扬子准地台西缘的红河深断裂北东侧,其中大红山铁矿Ⅱ1号矿组主要产于元古界大红山群红山组一段变钠质熔岩中,矿组严格受地层控制,为火山喷发—沉积变质形成的铁矿床。     

从榴辉岩与围岩的关系论苏鲁榴辉岩的形成与折返

位于华北和扬子两板块碰撞带中的苏鲁榴辉岩形成的温压条件不但是超高压，而且是高温。榴辉岩的PTt轨迹表明其为陆-陆磁撞俯冲带的产物。榴辉岩的区域性围岩花岗质片麻岩为新元古代同碰撞期花岗岩，榴辉岩及其他直接围岩皆呈包体存在于其中，并见新元古代花岗岩呈脉状侵入榴辉岩包体中。区域性围岩新元古代花岗岩的锆石中发现有柯石英、绿辉石等包裹体，表明新元古代花岗岩的组成物质也经受过超高压变质作用，且榴辉岩与围岩新元古代花岗岩的锆石U-Pb体系同位素年龄基本相同。但新元古代花岗岩所记录的变质作用和变形作用期次（或阶段）却少于榴辉岩。椐上述可得如下推断：超高压榴辉岩与新元古代花岗岩岩浆是同时在碰撞带底部（俯冲板块前部）形成的；榴辉岩的第一折返阶段是由新元古代花岗岩岩浆携带上升的，其第二折返阶段是和新元古代花岗岩一起由逆冲及区域性隆起而上升，遭受剥蚀。     

某高速公路下伏煤矿采空区稳定性分析

在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。      

摩擦桩基桩土间极限摩阻力取值问题探讨

通过对广珠东线高速公路横沥大桥的试桩及土体的工程地质条件分析,总结出影响摩擦桩基桩土间极限摩阻力取值的一般问题以及解决问题的方法和措施。     

The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads

In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.     

混凝剂处理钻井废泥浆液的研究

通过烧杯搅拌实验对混凝剂处理钻井废泥浆液进行研究,从混凝剂适应p H值范围、混凝效果、沉降速度三方面研究比较,找出一种较为理想的混凝剂,并分析了影响混凝剂性能的主要因素,确定了混凝剂的最佳投放剂量。      

黄河源区水环境变化及黄河出现冬季断流的原因

自1954年有水文观测资料以来，黄河曾在青海省玛多县黄河沿水文站发生过3次断流。本文在分析黄河源区水环境特征及其影响因素的基础上指出，鄂陵湖、扎陵湖的环湖融区调节能力低，当遇到连续干旱、冬季其调节水量不足以维系黄河径流时便会发生断流，这是断流的主因。湖水位降低、开采沙金、过度放牧等自然和人为因素也会对黄河发生断流产生影响。鄂陵湖口附近黄河上修建的水电站开始蓄水，提高了两湖及环湖融区的调节能力，今后黄河冬季出现断流的可能性将大为降低。     

Unity of the national and the international in the socio-cultural development of the peoples of the USSR

International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.     

Artemia in the Salt Lakes of Russia:the Productivity of Populations,the Reserves of the Cysts and the Fisheries

正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the     

天山南坡科其喀尔冰川表碛区小气候特征研究

利用天山南坡科其喀尔冰川3号观测站2009年全年的气象观测资料,分析研究了科其喀尔冰川表碛区的小气候特征. 结果表明：总辐射和净辐射夏秋季较高、冬春季较低;反射辐射和地表反照率反之. 与其他地区不同,该区主要受积雪物理性质和下垫面状况的影响,冬春季地表反照率日变化表现为由大到小的变化过程,夏秋季表现为倒U型. 温度年变化表现为夏秋季高、冬春季低,最高月均值出现在8月,为9.4℃,最低月均值出现在1月,为-9.6℃. 受山谷风和冰川风的影响,全年的风向以西北风和西北偏西风为主,风向的日变化以11：00为界发生转向. 受降水和冰川消融等的影响,比湿夏秋季月均值较大,冬春季月均值较小.     

The evolution of the magmatism in the external zones of the Betic Cordilleras during the mesozoic

Abstract

The Mesozoic igneous rocks from the External Zones of the Betic Cordilleras extend for some 300 km along the Subbetic Zone. They are poorly differentiated basic rocks which, altogether, correspond to a transitional series containing tholeiitic and sodium-alkaline terms. They crop out as small ophite stocks and dykes intruded into middle- and upper-Triassic rocks, or as submarine flows and sills interlayered with Jurassic materials.

Geological and radiometric evidence points to an upper-Triassic-Liassic age for the ophite-generating magmatism, while the fissure volcanism began locally in the early-Liassic and extended throughout the Dogger. It reached its climax in the Tithonian and ceased abruptly in the lowermost Cretaceous.

The magmas that generated the two groups of rocks originated within the mantle. During the ascent through a continental crust they were contaminated by deep-crust granitoid rocks and by the assimilation of pelites from the basement. The chemical composition and fractional-crystallization differentiation trends of the ophites belong to the tholeiitic series, while those of the middle-uppermost Jurassic magmas to the sodic-alkaline series. This magmatic evolution may be attributed to a geodynamic change from distensive in the Triassic to transtensive from the middle-Jurassic onwards.