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1.
介绍了蒋村铀钼矿成矿地质特征、火山角砾岩筒的形成及地质特征,该矿的下坑火山角砾岩筒是一个早、晚两期叠加的复式岩筒,早期为开启式爆发,晚期为封闭式隐爆,对成矿十分有利.分析了铀钼矿化控制因素及富集规律,认为铀钼矿化与断裂构造及火山角砾岩筒关系极其密切,断裂构造及火山角砾岩筒对铀钼矿化有着重要的控制作用.  相似文献   

2.
衡阳盆地大地构造处于华南板块与扬子板块相结合的钦-杭成矿带西段,属钦杭成矿带中部与南岭东西向构造-岩浆-成矿带中段北缘交会区。铜多金属矿床均分布在中新生代断陷盆地中及周边,其受区域上构造演化特定时期断陷盆地控制下的统一构造岩浆(火山)热液活动的制约,与深大断裂及其交会区强烈的构造-岩浆(火山)热液活动密切相关,主成矿时代为中-新生代。成矿规律分析表明,对于区内与构造-岩浆侵入作用有关的铜多金属成矿类型,自岩体向外呈现为:岩体内带型钨-锡-铜-铀-钠长石矿床→岩体接触外带型铀-铜-铅锌-钨-铁矿床→矽卡岩型铁-铜-铅锌(金)矿床→充填交代型铜-铅锌-重晶石-萤石矿床的水平和垂向分带特征。  相似文献   

3.
攀西地区金属成矿系统   总被引:4,自引:0,他引:4  
在简要分析了攀西地区基底演化、裂谷叠加、峨眉火成岩省、喜马拉雅期构造-岩浆-流体活动等重大地质事件及其成矿作用的基础上,将该区金属成矿划分为5个成矿系统,14个成矿亚系统,即:元古宇与火山-沉积-变质作用有关的铁铜成矿系统;晋宁-澄江期岩浆-热液成矿系统;新元古-早古生代沉积-改造型铅锌多金属成矿系统;峨眉火成岩省成矿系统;喜马拉雅期构造-岩浆-流体活动成矿系统。并论述了主要成矿系统的组成、结构及成矿规律。  相似文献   

4.
兰坪-思茅盆地区域构造及铜多金属成矿演化   总被引:3,自引:0,他引:3  
区域成矿演化受控于区域构造演化,是成矿规律研究中的重要内容.通过对兰坪-思茅地区区域构造演化与成矿系统关系研究,指出该区早古生代以来大地构造演化经历了原特提斯-古特提开启-闭合及多陆块相互作用时期(Pz1-T2)、新特提斯的开启及盆地形成时期(T3-K)和陆内碰撞造山及盆-岭构造系统形成时期(E-Q).伴随构造演化,铜的成矿大致经历了弧后裂谷火山喷流-沉积成矿(S)→洋盆喷流-沉积成矿(Pz2)→俯冲碰撞带幔源岩浆铜镍硫化物成矿(P)→岛弧火山热液及火山沉积成矿(P-T2)→前陆盆地热水沉积成矿(T3)→红层盆地热卤水成矿(J-E)的演化过程.其中,火山喷流沉积型、铜镍硫化物型和改造型是相对重要的3种成矿类型.  相似文献   

5.
吉林延边地区中生代火山岩金铜成矿系列及区域成矿模式   总被引:9,自引:0,他引:9  
延边地区为我国东部滨太平洋的一个重要金、铜-(多金属)矿化集中区。成矿带在时、空和物质组成上主要受控于中生代火山-岩浆侵入作用,形成多种金、铜矿床类型组合的成矿带,在分析成矿带内不同矿床成因类型的基础上,建立了该成矿带的成矿系列,即斑岩铜钼、火山热液金银、次火山热液金银铅锌成矿系列,将成矿系列控矿条件和火山-岩浆侵入作用相结合,探讨成矿系列的构造环境和成矿模式。  相似文献   

6.
研究区位于柴达木盆地北缘内生矿产成矿带东段。依据区域地质、构造演化和铀矿化特征,分析了构造-岩浆演化,主要含铀建造包括古元古代达肯大坂群、奥陶-志留系滩涧山群和上泥盆世牦牛山组,加里东、华力西和印支期岩浆活动,北西向断裂带控制地层、岩体及铀矿化展布等铀成矿条件,认为研究区铀矿化受含铀建造、北西向断裂带及华力西-印支期中酸性岩浆活动"三位一体"控制,进而探讨了柴达木东北缘铀矿找矿远景。  相似文献   

7.
衡阳盆地大地构造处于华南板块与扬子板块相结合的钦-杭成矿带西段,属钦杭成矿带中部与南岭东西向构造-岩浆-成矿带中段北缘交汇区.铜多金属矿床均分布在中新生代断陷盆地中及周边,其受区域上构造演化特定时期断陷盆地控制下的统一构造岩浆(火山)热液活动的制约,与深大断裂及其交会区强烈的构造-岩浆(火山)热液活动密切相关,主成矿时...  相似文献   

8.
山西堡子湾金矿床地质特征及成矿规律   总被引:4,自引:0,他引:4  
矿床受大吴窑-胡窑张扭性断裂带构造控制,矿体产于堡子湾隐爆角砾岩体中,成矿物质主要来自地壳深部岩浆源。矿床属与次火山隐爆作用有关的中-低温热液矿床。  相似文献   

9.
方芳 《河南科学》2019,37(9):1503-1511
南沟金(萤石)矿床位于华北板块南缘,秦岭造山带北秦岭构造亚东的东段,马超营区域性脆韧性断层的北侧.成矿受太古界太华群地层、基底背斜构造和断层(环形构造近EW向及NW向断裂构造)及燕山期晚期岩浆侵入活动作用等三重地质要素的控制.成矿物质来源多样,如燕山期晚期花岗岩体、太古界太华群地层.金矿石铅、硫同位素测试结果表明,成矿流体来自地壳深部或上地幔.该矿床大地构造成矿环境、赋矿围岩特征、控矿构造及岩浆岩条件等矿化特征均与造山型金矿相似,成矿作用多样(火山喷流沉积、变质作用改造,岩浆热液作用交代等),矿床成因为叠生复合造山型金(萤石)矿.  相似文献   

10.
北淮阳构造带东段金-多金属矿床区域成矿规律   总被引:12,自引:0,他引:12  
北淮阳构造带东段是我国秦岭-大别成矿带的重要组成部分,该区金及铅锌多金属矿床较发育。成矿作用主要受燕山期构造-岩浆活动事件控制,矿床在空间上沿区域性的断裂分布,时间上以燕山期成矿为主,成矿物质来源有幔源和壳源,但以壳源为主。文章在对区内的矿化集中区及相关矿床深入分析的基础上,论述了区域成矿地质背景和成矿规律,并指出了今后的找矿方向。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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