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1.
对我国西南地区以往铀矿勘查工作成果与认识进行了总结论述,展望了今后铀矿勘查的突破方向。西南地区铀资源勘查工作始于1955年,已探明铀矿床在区域上形成了五个铀矿田。根据区域铀成矿特点和控制区域构造单元的级别,结合铀矿床、矿(化)点的集中程度等,可划分为五个成矿带和四个成矿远景带。通过对主要铀成矿带内铀矿田(床)区域成矿地质背景、控矿因素、矿化成因等的研究,认为西南地区铀成矿地质条件有利,下一步铀资源勘查突破方向是扩大老矿区,开辟新基地。  相似文献   

2.
介绍了地面伽玛能谱和土壤天然热释光测量组合在河元背铀矿床近外围地区普查找矿中的应用效果;在对异常解释、推断的基础上,结合区内铀成矿地质背景及地面伽玛能谱和土壤天然热释光测量异常与已知矿床间的对应关系,圈出了4个找矿靶区;对其中的3号和4号靶区所在区域开展了进一步的铀矿普查工作,通过勘探在深部发现了受南北向苦命山-小陂断裂带控制的铀矿带,表明这两种方法组合可以较好地提供深部铀矿化信息,是该地区寻找隐伏铀矿体的一种有效的勘查方法组合.  相似文献   

3.
探讨四川若尔盖铀矿田铀的成矿地质条件,为成矿预测和找矿靶区选择提供依据。通过对若尔盖铀矿田主要矿床的野外地质调查、资料的综合分析研究,结果表明若尔盖铀矿的形成与富铀古陆块、富铀沉积建造、多期次的岩浆活动和富铀岩体、区域性深大断裂带、中新生代陆相红色砂砾岩盆地、有利的岩石组合及其物理力学性质等区域地质背景和条件有着十分密切的关系。若尔盖铀矿田西部矿带的集中分布和一系列有利于铀成矿的良好地质条件,表明若尔盖地区是铀成矿的有利地区,仍存在寻找隐伏富大铀矿的巨大潜力。  相似文献   

4.
黑山地区位于祁漫塔格多金属成矿带,近年来该带上发现的铅、锌、铁等矿产较多,而铀矿找矿方面至今没有取得大的进展。黑山地区众多铀异常、点带及铀矿点的发现在一定程度上填补了该带上铀矿产的空白。本文以黑山铀矿点为例,从黑山地区地层、构造、岩浆岩、铀矿化特征、热液活动及围岩蚀变等方面入手,对黑山地区铀成矿地质条件进行了阐述,进而对本区铀成矿远景做了初步分析,提出今后找矿的远景地段。  相似文献   

5.
基于前人区域地质研究成果和本单位在芙蓉地区历史铀矿勘探资料,归纳分析该地区铀成矿地质条件,评价其铀矿找矿潜力。研究表明,芙蓉地区隶属于雪峰山-摩天岭铀成矿带雪峰山铀成矿亚带;发育震旦系、寒武系、二叠系黑色岩系、碳酸盐岩、硅质岩及砂岩等富铀岩石组合,是中南地区最重要的富铀层位;该区印支晚期-燕山期多期次岩浆活动强烈,趋向于钾质富集、白云母化较发育,岩体铀含量高;存在大规模的基底断裂构造,具有控岩、控盆和控矿作用,构造活动持续较长时间、具多方向性,低序次低级别构造发育;以往铀矿地质勘查工作中,探明了一些铀矿产,发现了大量铀矿化(异常)点带,放射性物探和水化学异常发育。该地区与鹿井铀矿田在区域地质背景、铀成矿地质条件方面具有很大程度的相似性,具有良好的铀成矿条件和找矿潜力。  相似文献   

6.
鹿井地区铀矿勘查工作始于1958年,至20世纪90年代结束,已落实为鹿井铀矿田.2009~2012年间核工业270研究所在该区开展了铀成矿潜力评价及普查找矿工作,取得了一系列的勘查成果.介绍了鹿井铀矿田的地质概况及地球物理场和地球化学场特征.重点介绍了区域布格重力场特征;区域航磁异常特征;航空伽玛能谱场特征.根据遥感影象资料,认为丰州盆地正好处在一个大的环形构造中,而且在盆地西北部,也可清晰的见到较小的环形构造.结合环形构造的边缘分布有花岗岩杂岩体,鹿井矿田铀矿床与火山塌陷中的环状花岗岩杂岩紧密相伴,铀矿体主要分布在环状杂岩体顶部、旁侧等接触变异部位.丰州盆地具有较好的铀成矿远景.  相似文献   

7.
连山关地区铀成矿研究已形成大量的文献,笔者从基础地质研究入手,综合前人的矿床学研究成果,认为该区主要铀矿类型为与脆~韧性剪切带相关联的热液脉型铀矿化—以连山关铀矿床为典型代表。脆—韧性剪切作用的存在是形成铀矿化的重要因素,赋存围岩为断层构造岩,其成矿热液来自于深成变质水、构造热液及部分深源岩浆水。在总结了该区的找矿标志的基础上,提出了三个远景区段。  相似文献   

8.
通过总结白杨河铀铍矿床主要控矿因素,分析其地球化学特征及与成矿的作用关系,指出白杨河铀铍矿床区域地球化学背景具有较好的铀铍成矿前景。矿体主要赋存于花岗斑岩与泥盆系火山熔岩、火山碎屑岩的接触带部位,其中花岗斑岩为主要铀源体,中酸性围岩则为成矿富集提供了有利的地球化学障;南北接触带为矿区内重要的含矿和控矿构造,其矿化蚀变及微量元素差异说明铀与铍非同期产出物;该区含矿花岗斑岩蚀变最发育,矿化关系密切的围岩蚀变主要是赤铁矿化和萤石化,据不同蚀变程度微量元素对比发现Pb、Mo等元素可作为铀矿化蚀变的指示元素。  相似文献   

9.
在详细阐述石洞矿床地质特征的基础上,着重对矿床及其外围放射性伽玛场特征及成矿期构造活动进行了研究,认为NW向构造是矿床的控矿构造,构造界面是重要的成矿地质界面,放射性伽玛场及异常点受构造控制,并对深部隐伏铀矿化具直接指示作用。晚成矿期,NE向邹家山—石洞构造左旋走滑,NW向构造在NE向构造两侧错移并发生张扭破碎,为矿质卸载提供了空间。矿床内F4,F5及可能存在的隐伏F6构造,具有较大的找矿空间和找矿潜力,矿床规模可望达到大型。  相似文献   

10.
塔然高勒铀矿床是东胜铀矿田内新发现的大型地浸砂岩型铀矿床。为研究该矿床的地球化学特征,系统采取了矿床内钻孔岩芯样品21件,通过等离子质谱、荧光光谱、电镜扫描等分析方法,对矿体上部的绿色砂岩、矿体下部的灰色砂岩和含矿的灰色砂岩开展了主量元素、微量元素、稀土元素的地球化学特征研究及铀矿物与黄铁矿、粘土矿物等共生组合关系研究。研究结果表明矿床内铀矿物主要为铀石;黏土矿物与成矿关系密切,在铀成矿过程中可吸附铀元素,使铀富集成矿;钇元素可以作为塔然高勒铀矿床内铀矿化的指示元素,钼元素可以作为铀矿化的参照元素;稀土元素主要赋存在铀矿石中,与铀共生。本研究成果对铀矿床的下一步勘查和铀矿冶工作具有重要的指导意义。  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.
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   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
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   

17.
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   

18.
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   

19.
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   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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