首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 343 毫秒
1.
东昆仑祁漫塔格地区位于东昆仑F e-Pb-Zn-Cu-Co-A u-W-Sn-多金属-盐类成矿带中,随着地质勘查进程的不断深入,该区现已成为铁矿、钨锡矿、铜矿、铅锌矿等矿产的矿集区,其地质找矿潜力非常巨大。笔者从成矿地质条件、区域地球物理场、区域地球化学场等角度对鸭子泉—维宝地区的成矿规律进行了剖析,并结合白干湖钨锡矿、维宝铅锌矿等典型矿床的特征对区内的各主要成矿元素的成矿类型、成矿期次进行了较为系统的归纳,认为该区具有寻找岩浆热液型钨锡矿、层控型铅锌矿、矽卡岩型铁铜多金属矿等矿产的有利地质条件,并对以上各类型矿床的产出环境、成矿时代、沉积(变质)建造、岩浆建造、控矿构造等成矿地质条件进行了总结,建立了区域成矿模式。  相似文献   

2.
青海省东昆仑野马泉铁多金属矿床处于野马泉—开木棋河华里西期铅、锌、钴(金、锑、锡、铋)成矿亚带中,矿床规模达中型以上,是东昆仑地区重要的铁多金属矿床之一。通过分析矿床地质特征、矿体特征、围岩蚀变及控矿规律,认为铁多金属矿的成矿受印支期中酸性侵入岩、热液蚀变和晚石炭世缔敖苏组碳酸盐岩建造的控制,已发现的矿体赋存于岩体外接触带及附近的断裂带中,远离接触带铁矿体的规模逐渐变小,具有夕卡岩型矿床的基本特征。依据控矿因素特点,探讨了该类铁多金属矿床的勘查模型。  相似文献   

3.
位于山东省南部苍山-枣庄地区的苍峄铁矿带是一条大型沉积变质型铁矿带,其铁矿储量巨大。为了更好地适应新形势下的铁矿勘查工作,建立了该区的铁矿预测找矿模型,以期提高区内铁矿勘查效率。简要介绍了区内铁矿成矿地质背景,并详细阐明了南山村地区铁矿床特征:该矿床赋存于新太古代泰山岩群山草峪组中;铁矿体的产状呈层状、似层状;矿石为磁铁角闪石英岩和磁铁石英岩,属需选弱磁性铁矿石,为“鞍山式”贫铁矿。区内水文地质条件属简单-中等类型,工程地质属简单类型,环境地质属中等类型。区内的勘查工作证实,明显的磁异常部位是该铁矿带最重要的找矿标志之一。从岩石类型、成矿时代、含矿地层、含矿建造、控矿构造、矿物组合、结构构造、矿体产状、磁异常、重力异常和地形地貌方面建立了苍峄铁矿带的区域综合预测找矿模型。  相似文献   

4.
矿产资源评价系统及其在东昆仑的应用   总被引:7,自引:2,他引:5  
多元信息成矿预测是一种高效、高质量的找矿勘查方法,代表了当今找矿评价工作中的主流发展趋势,该方法是以成矿地质理论为指导、以地物化遥异常理论为依托、借助数学方法和计算机技术对地物化遥异常中的各种与矿床有关的信息进行量化分析,从而进行成矿预测的一种找矿勘查技术方法。本研究的重点是应用矿产资源评价系统,分析和运用研究区的地质、地球化学和地球物理信息,构造预测变量,将各种有利于矿床形成的变量进行成矿有利度得分和多源信息综合定量分析,在此基础上,综合分析东昆仑地区地质、矿产、地球物理和地球化学信息,根据已知矿床反映出的成矿规律、控矿条件及找矿标志建立找矿模型,对东昆仑地区进行了1:50万综合成矿预测,获得Sedex型矿床在东昆仑地区的成矿有利度分布,并圈定出找矿远景区。为东昆仑地区找矿预测提供了重要依据。  相似文献   

5.
大坪铁锰矿为典型"虎牙式"矿床,通过对矿床特征、古地理特征及控矿构造分析,认为区内成矿地质条件好,找矿潜力较大。对区内铁锰矿勘查具有指导意义。  相似文献   

6.
安徽铜官山矿床成矿地质特征及深部成矿预测   总被引:2,自引:0,他引:2       下载免费PDF全文
文章在分析铜官山矿床成矿地质背景和成矿地质特征基础上,根据铜陵地区层控夕卡岩铜矿成矿规律和控矿特征,对铜官山矿床宝山矿段和罗家村矿段深部成矿条件和找矿前景进行了预测,认为该两区段深部具有一定找矿潜力.  相似文献   

7.
通过介绍东昆仑夏日哈木铜镍硫化物矿床的发现,以及对矿床特征的初步研究,进一步阐明"小岩体成大矿"的地质事实及这一理论对勘查找矿工作的理论指导和实践意义。同时阐明该矿床的发现昭示区内该类型矿床具有巨大的成矿潜力,其对东昆仑地区寻找同类矿床具有重大指导意义。  相似文献   

8.
崔伟 《地质与勘探》2022,58(5):989-1000
铁矿是重要的大宗金属矿产资源,冀东地区作为我国重要的钢铁基地面临着后备资源不足的问题,亟待深入开展冀东地区铁矿成矿规律和找矿方向研究。本文在近年来冀东地区找矿实践的基础上,利用勘查区找矿预测理论方法体系,系统归纳冀东铁矿床特征,共划分5个成矿区带,分析了本区鞍山式沉积变质型铁矿含铁建造、变质变形空间分带规律及控矿构造特征,并总结该地区矿床成矿规律。提出滦县滦南铁矿成矿区带成矿构造受背形和断裂构造共同控制的观点,指出冀东地区“就矿找矿”预测要素可简化为矿体控制程度和地球物理标志两大类。认为冀东铁矿地质工作程度高,进一步找矿的2个主要方向:一是已有大中型矿山深部和外围“就矿找矿”,预测其仍有较大资源潜力;二是迁安铁矿成矿区带第三层硅铁建造,属新发现的成矿空间,具有重要的找矿意义。  相似文献   

9.
大红山地区是云南省重要矿集区之一,已发现大红山大型铁铜矿床及东么、底巴都、底戛母、河口、坝达等多个中小型铁铜矿床(点),区内分布多个磁异常及化探异常,成矿地质条件优越。近年云南省三年地质找矿行动计划项目“云南省新平县大红山外围铁、铜矿资源普查”经过勘查在大红山外围东么、底巴都矿区圈定多个工业铁、铜矿体及超贫磁铁矿体,取得一定找矿新进展。本文根据近年工作中观察到的新现象、取得的新资料,结合前人研究成果,对大红山地区铁、铜矿床成因类型及形成机理进行探讨。  相似文献   

10.
山东省地处中国东部, 经历了漫长地质演化历史, 分为鲁西和鲁东2个主要地块, 地质矿产具有各自鲜明的特征; 其中区内铁矿成矿地质条件优越, 成因类型多样, 矿床广泛分布, 资源储量丰富, 是全国重要的铁矿开发基地。本次研究旨在通过对全省地质矿产资料进行总结, 从地层赋矿、构造控矿、岩浆岩成矿和物探异常示矿等方面对全省铁矿成矿规律进行分析, 进一步对全省铁矿资源潜力进行研究。研究表明全省铁矿类型共分苍峄式、莱芜市、莲子汪式、朱崖式等共14个矿床式; 铁矿成矿规律研究表明, 各铁矿类型受到地质构造演化控矿、地层控矿、岩体控矿、构造控矿等控制程度不同; 如地层控矿方面尤以沉积变质型、化学沉积型较为突出, 岩体控矿方面尤以岩浆型铁矿最为显著, 而接触交代型铁矿则是地层控矿、岩体控矿、构造控矿联合作用的结果。随着深部找矿工作的持续推进, 认真总结物探异常示矿规律是今后勘查工作的重点, 低缓磁异常区的勘查是取得重大进展的关键。通过对全区铁矿的时空分布特征对比分析和成矿规律研究, 划分了全省铁矿成矿系列, 并总结了综合找矿预测模型; 构建了研究区铁矿综合勘查技术体系。此次研究共圈定了苍峄铁矿远景区、莱芜铁矿远景区、淄河铁矿远景区和莱阳西铁矿远景区等36处; 其中沉积变质型铁矿共15处, 接触交代型铁矿共9处, 岩浆热液型铁矿共4处, 岩浆型铁矿共8处; 在上述36处远景区中, A类远景区共18处, B类远景区共13处, C类远景区共5处, 在今后各个铁矿类型勘查过程中, 沉积变质型铁矿和接触交代型铁矿是今后勘查工作的重点。本次研究为今后全省铁矿找矿工作提供了部署依据和勘查方向。  相似文献   

11.
微亮晶(臼齿)碳酸盐成因及其在元古宙地球演化中的意义   总被引:14,自引:2,他引:14  
本文应用多种技术方法,对微亮晶碳酸盐岩的成岩作用及其成因从宏观至微观进行了分析。根据岩石矿物学、地球化学和有机地球化学等研究证明,它是早期成岩过程中,在超高压的大气 CO_2,水平急剧下降的转折期,快速石化作用形成的具等粒结构μm级的微亮晶方解石集合体。MT 碳酸盐岩微亮晶成岩作用有两种类型:一是主要发生在海底沉积软泥中,在其底基质软泥中经差异压实作用形成褶皱肠状及复杂形的 MT 构造;二是直接在海水中或重力流搬运过程中形成的微亮晶球粒(核)。简言之,MT 碳酸盐岩石是在地球早期浅海环境下,由于微生物自养作用形成的地球化学成因产物。微亮晶碳酸盐岩是约束古大气圈和古海洋环境变化的最灵敏标志。通过详测 MT 丰度值和编制地球古大气圈 CO_2水平演化模式等,在前寒武纪发现有太古宙末期、早元古宙末期、中元古宙中期和新元古宙早-中期四个 MT 碳酸盐岩发育高峰值期,证明全球古大气圈 CO_2水平发生过四次不连续性、跳跃式下降周期,直到晚新元古宙未,全球雪球事件的发生,导致了 MT 碳酸盐岩的消失。其后,才进入显生宙的 CO_2低水平状态。MT 碳酸盐岩具有重要的油气资源远景,应予以重视。  相似文献   

12.
The composition and distribution of phenanthrenes (polyaromatic compounds) have been studied in chloroform extracts from dispersed organic matter (OM) of clayey, siliceous, carbonate, and terrigenous rocks of different ages and facies and from some oils of the Siberian Platform. Phenanthrenes have been analyzed by gas chromatography-mass spectrometry. High contents of 1,7,8-trimethylphenanthrene and 1,1,7,8-tetramethyl-1,2,3,4-tetrahydrophenanthrene are present in the OM of Vendian and Cambrian carbonate-shale deposits and in ancient oils of the Nepa-Botuobiya and Anabar anteclises. The OM of Permian continental deposits and oils of the Vilyui syneclise is dominated by 1-methyl-7-isopropylphenanthrene (retene). A triangular diagram for identification of the types of original OM of rocks and classification of genetically related oils has been constructed based on the assessment of phenanthrene biomarker distribution. Putative pathways of the formation of phenanthrene biomarkers are discussed.  相似文献   

13.
我国中西部前陆盆地的特殊性和多样性及其天然气勘探   总被引:7,自引:0,他引:7  
通过对我国中西部前陆盆地构造特征、大地构造背景、地球物理特征的理论研究和典型前陆盆地的详细解析,系统分析了我国中西部前陆盆地的发育特征和特殊性。强调晚二叠世以来大小不一、形态各异的多块体小型克拉通的聚合碰撞作用是导致中西部前陆盆地群形成的基本动力学过程:这些小型克拉通的多块体聚合碰撞造就了中西部前陆盆地的特殊性和多样性。同时,明确提出中西部盆地的基本特点是“两期三类前陆盆地”,即海西一印支期前陆盆地和喜山期前陆盆地,三类指海西一印支期的周缘前陆盆地和弧后前陆盆地、喜山期再生前陆盆地。根据前陆盆地的盆地结构和演化特征,又将中西部的前陆盆地划分为4种组合形式,即叠合型组合、改造型组合、早衰型组合和新生型组合。综合论述了不同时期不同类型前陆盆地构造对天然气聚集的五大控制作用。  相似文献   

14.
Chronological analyses of correlations between certain global repeating events (mass extinctions of marine organisms, meteorite impacts, and flashes in the frequency of geomagnetic reversals) during the Phanerozoic Eon and the motion of the solar system in the Galaxy are presented for five rotationally symmetrical models for the regular Galactic gravitational field. Thirteen of sixteen mass-extinction events can be described by a repetition interval of 183±3 million years. This is in agreement with the anomalistic period (interval between two subsequent passages of the Sun through the apocenter of its Galactic orbit) in the model of Allen and Martos. The positions of the minima and maxima in Gaussian functions approximating the frequency distribution for geomagnetic reversals also agree with the times of passage of the Sun through the apocenter and pericenter, respectively, of its Galactic orbit in this model. The maximum in the distribution of the deviations of the dates of mass extinctions from the nearest dates of impacts of large, crater-forming bodies is close to zero, providing evidence that many such events are correlated. As a rule, extinctions follow impact events. The impacts of large bodies have occurred most often when the solar system passes through the Galactic plane, while mass extinctions occur more often at some distance from the Galactic plane (about 40 pc). As a rule, intervals of increases in the frequency of geomagnetic reversals coincide with dates of impacts of large bodies. At the same time, these intervals do not show a clear correlation with the dates of mass extinctions. The intensity of mass extinctions, like the energy released by impacts, is consistently higher in periods when the Sun is moving from the apocenter toward the pericenter of its orbit, than when it is moving from the pericenter toward the apocenter. Thus, there is evidence for a variety of relationships between repeating global events in the Phanerozoic and the motion of the Sun in the Galaxy. Long-period variations in the frequency of geomagnetic reversals are correlated with the orbital motion of the Sun, and increases in the frequency of geomagnetic reversals are correlated with impacts. Mass extinctions are correlated with the impacts of large bodies, whose motions may have been perturbed by clouds of interstellar material concentrated toward the Galactic plane and by the shock front associated with the Perseus spiral arm, through which the solar system passes. The velocity of the Sun relative to the spiral pattern is estimated.  相似文献   

15.
Silicon is a key element whose major role in the control of the cycle of carbon in the ocean has been recently revealed. This is first illustrated through the resolution of the ‘opal paradox’ in the modern Southern Ocean. Second, the ‘silica hypothesis’ explains why, during the Last Glacial Maximum, the atmospheric concentration of CO2 was about 40 % below that of the interglacial period. Increased deliveries of wind-borne silica to the surface ocean as well as of riverine inputs favoured the dominance of diatoms over coccolithophorids, resulting in a net emission decrease of CO2 by coccolithophorids from the ocean surface to the atmosphere. To cite this article: P. Tréguer, C. R. Geoscience 334 (2002) 3–11  相似文献   

16.
北极地区丰富的油气资源近年来引发全世界的广泛关注。评估结果显示,北极油气资源分布不均,主要集中在俄罗斯、美国阿拉斯加、挪威、加拿大和丹麦格陵兰。不同国家和地区北极油气资源勘探开发特点不同,在新形势下可能还会发生变化。中国是油气消费大国和进口大国,俄罗斯北极地区已日渐成为中国重要油气供应地之一。综合分析几个主要北极国家北极油气开发利用现状和未来发展前景,与中国目前参与北极油气开发利用的情况,对未来中国如何参与北极油气资源开发利用提出建议,将俄罗斯作为中国北极油气开发的长期合作伙伴,与其开展项目投资、技术入股、航道建设等多个方面的合作。   相似文献   

17.
The magmatic and tectonic activity of eastern South America and the western South Atlantic shows that extension of the continental crust is the determinant factor of magmatism. Heating of the upper mantle is a necessary condition of its manifestation. Ascending plume material is a source of additional heat. In the Early Mesozoic, Eastern Brazil was situated above a large, ascending and probably ramifying plume, which has supplied heat and material since the Triassic, creating favorable conditions for continental magmatism. Magmatic activity continued, gradually waning, until the Neogene as evidence for long-term retention of heat energy beneath the continental lithosphere after the plume ascent. It has been shown that heated mantle material can be displaced from the continent to the ocean for a significant distance beneath the lithosphere with the formation of linear tectonomagmatic rises of the oceanic crust. The structural elements inherited certain directions on the continent and in the ocean, beginning from the Neoproterozoic. These directions were reactivated and continued to control the younger structural grain and magmatic activity. In Southeastern Brazil, these were the structural units striking in the southeastern (about 120° SE) and northeastern directions parallel to the continent-ocean boundary. In Northeastern Brazil, the W-E- and N—S-trending structural units are predominant. All these directions are manifested in oceanic structural units (Rio Grande, Vitória-Trindadi, Fernando de Noronha, Pernambuco rises, etc.).  相似文献   

18.
西北地区盐渍化土地开发中存在问题及防治对策   总被引:3,自引:0,他引:3  
马传明  靳孟贵 《水文》2007,27(1):78-81
在分析我国西北地区盐溃化土地形成机制的基础上,着重研究了西北地区盐渍化土地开发利用过程中所引发的环境问题:上游灌区土地次生盐渍化、水肥利用效率低,下游地区水土污染、水资源短缺、生态恶化,最后给出了相应的防治对策和建议。  相似文献   

19.
Variations in the tree line position and glacier activity in the Central and Eastern Altai regions in the Holocene were reconstructed on the basis of analysis of sixty radiocarbon and eighteen dendrochronological dates. The tree line was higher than now in the Early and Middle Holocene, and the climate was warmer and, likely, more humid. Glaciers advanced in the forests 300, 1400, and 3000–6000 years ago. In the last millennium the forest decline at the upper tree limit occurred in 1206–1256, 1445–1501, and 1642–1736.  相似文献   

20.
国际埃迪卡拉系年代地层学研究进展与发展趋势   总被引:2,自引:0,他引:2  
埃迪卡拉系为国际地层表新增的新元古界最上部的系级年代地层单位,层型剖面被确定为南澳大利亚弗林德斯山脉依诺拉马河剖面,其底界点位(GSSP)选定为埃拉逖那冰成杂砾岩(Elatina diamictite)之上盖帽碳酸盐岩努卡利那组(Nuccaleena Formation)的下界(Gradstein et al.,2004;Knoll et al.,2004)。我国修定后的震旦系与埃迪卡拉系完全相当,底界以南沱冰碛岩之上盖帽碳酸盐岩的下界为界。本文综合国际地层委员会新元古代地层分会以及相关国家和地区近年来在埃迪卡拉系年代地层学领域研究的新进展、存在问题以及未来发展趋势作一概要介绍,以期引起国内晚前寒武纪地层古生物学者的广泛关注。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号