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1.
山东招平断裂带大磨曲家金矿床流体包裹体初步研究   总被引:1,自引:0,他引:1  
The Damoqujia gold deposit, discovered recently and located in the north of Zhaoping fault zone, is a large altered rock type deposit. In this paper, we report the preliminary research results of the fluid inclusions and discuss its metallogenic implications. The homogenization temperatures of fluid inclusions fall into four ranges: 310 ~350℃, 230 ~270℃, 160 ~ 200℃ and 110 ~ 150℃ ; corresponding to the four stages of hydrothermal ore~forming processes : coarse grain pyrite~milk white quartz stage ( I ), smoky gray Au~bearing quartz~fine grain pyrite stage ( 11 ) , Au~bearing polymetallic sulfide~quartz stage ( III ) , and quartz~carbonate stage ( IV ). Ore~forming fluid is with low salinity and low density, ranging from 1.4 WtNacl% to 13.6 WtN~cl% and from 0.48g/cm~ to 1.03g/cm~ respectively. The inclusions are dominated by H20 and CO2 in gaseous compositions, and Na + and K ~ in positive ions, SO~~ and CI ~ in negative ions of liquid compositions. Au~S complex is the major form for transportation of gold. The pressure varied from 260MPa to 340MPa during the formation of CO2~bearing inclusions at the early mineralization; the fluids are rich in SO~~ and Na ". The pressure is 26 ~49 ~ 105 Pa during the formation of the aqueous salt inclusions in late mineralization, the inclusions are rich in CI~ ( F~ ), Na~. ~$18Oqu~,zis 10. 64 ~ 12.68%0, and the corresponding ~518 OH2o and ~&D is -5.44 ~ 6.47%0 and -95.52 ~ 106.48%o respectively. Based on the studies about compositions and hydrogen and oxygen isotopes of inclusions, it is evidenced that ore-forming fluid is magmatic hydrothermal fluid in early period, but affected by meteoric water in late.  相似文献   

2.
Melt and fluid inclusions were studied in the minerals of Cenozoic olivine melanephelinites from the Chukehi Peninsula, Russia. The rock contain several generations of olivine phenocrysts varying in composition at mg=0.88 - 0.77. The phenocrysts bear fluid and melt inclusions recording various stages of melt crystallization in volcanic conduits and shallow magma chambers. Primary fluid inclusions are CO2-dominated with a density of up to 0.93 g/cm^3. All fluid inclusions are partially leaked, which is indicated by haloes of tiny fluid bubbles around large fluid inclusions in minerals. Melt inclusions contain various daughter crystals, which were completely resorbed in thermometric experiments at about 1230~C. Assuming that this temperature corresponds to the entrapment conditions of the CO2 fluid inclusions, the minimum pressure of the beginning of magma degassing is estimated as 800MPa. Variations in the compositions of homogenized silicate melt inclusions indicate that olivine was the earliest crystalline phase followed by clinopyroxene, nepheline and orthoclase. This sequence is in agreement with the mineralogy of the rocks. The melts are strongly enriched in incompatible trace elements and volatiles (in addition to CO2 , high C1, F, and S contents were detected). There are some differences between the compositions of melts trapped in minerals from different samples. Variations in SiO2 , FeO, and incompatible element contents are probably related to melt generations at various levels in a homogeneous mantle reservoir.  相似文献   

3.
This paper is focused on the progress in the determination of water in glasses and melt inclusions with Raman spectroscopy. Using the presented "Comparator Technique" the water content of a sample is determined by siruple comparison with a known standard. A calibration curve is not necessary. Furthermore, with this technique the water concentration in silicate melt inclusions can be determined without exposing the inclusions for measurements. This is very important for extremely water-rich melt inclusions, which would loose H2O on exposure.  相似文献   

4.
Fluid inclusion study has been carried out for the carbonatite dykes/veins and the ore-hosted dolostone of the Bayan Obo superlarge REE-Fe-Nb deposit in order to provide the evidence and constraint for their origin. Based on the detailed geological observation and mineralogical investigation, the heating and cooling stage and laser Raman spectroscopy were mainly used for the laboratory work of this study. Following results have been obtained: ( 1 ) The discovery of melt and melt-fluid inclusions from carbonatite dykes/veins in the Dulahara and Jianshan Mountains, combined with the fine-grained (aplitic) texture of rocks, as well as the types and features of fluid inclusions such as CO2 enrichment, higher homogenization temperature, provides a direct evidence for the magmatic origin of these dykes/veins. (2) The carbonatite dykes/veins distributed in two regions, nearby the axis of the Kuangou anticline and in the east to Bayan Obo town, mainly show coarse-grained texture. No melt inclusion was found, and the fluid inclusions possess features of less CO2, lower homogenization temperature and higher salinity. They are tentatively identified as veins formed by some carbonate-rich hydrothermal solution. (3) Bedding carbonate layers/lens within the hanging wall and foot wall of ore-hosted dolostone, previously recognized as of magmatic origin, mainly composed by dolomite. The existence of single phase pure aqueous inclusions with very low homogenization temperature indicates their sedimentary origin. (4) The ore-hosted dolostone possesses apparent bedding and laminated structures. No melt inclusion was found, but, both single phase pure aqueous inclusions and CO2 bearing muhi-phase fluid inclusions coexisted in dolostones. In the direction towards ore-bodies, the homogenization temperature and CO2 contents of fluid inclusion show an increasing tendency. It indicates the sedimentary origin of dolostone superimposed by late fluid metasomatism.  相似文献   

5.
In this paper, solution to the LQ inverse problem has been pre-sented. With the control weight in an LQ optimal control system fixed,the state weighting matrix is parametrized in terms of a set of freevariables and the closed-loop eigenvalues of the control system. Basedon this parametrization, an algorithmic procedure is proposed to deter-mine the state weighting matrix and the free variables by matrixtransformation. Meanwhile, by using the solved free variables, theoptimal feedback gain matrix K can also be obtained without solving thealgebraic Riccati equation.  相似文献   

6.
The acoustic decrepitation method heats a small monomineralic sample and counts pressure impulses as the inclusions burst when they develop high internal pressures. For aqueous fluids, the decrepitation temperature is correlated with the homogenisation temperature, but gas rich fluids give a distinct and characteristic low temperature decrepitation peak which can be used to recognize gas rich fluid inclusions. This information is useful in exploration for Au deposits, which are frequently associated with CO2 rich and sometimes CH4 rich fluids. This distinctive decrepitation occurs because the CO2 rich inclusion fluids expand according to the gas law and develop internal pressures high enough to burst the host mineral grain at temperatures well below their homogenisation temperatures. In contrast, aqueous fluids condense to a liquid and vapour phase during post-entrapment cooling. Upon subsequent heating their internal pressures do not increase significantly until after homogenisation to a single phase occurs and hence they do not decrepitate "prematurely" as gas rich inclusions do. This behaviour is usually regarded as an annoyance in conventional microthermometric homogenisation studies, but can readily be used as an exploration aid to find mineralisation deposited from such gas rich fluids. Decrepitation results on samples from Cowra Ck, NSW, Australia, which have also been microthermometrically measured for CO2 content, show that amounts of less than 5 mole % CO2 are easily distinguished by decrepitation and amounts as low as 1 mole % CO2 may be determinable. Examples of the use of acoustic decrepitation in the study of 6 gold mines in the Shandong and Hebei provinces of China are discussed.  相似文献   

7.
Crystalline and melt inclusions were studied in garnet, diopside, potassium feldspar, and sphene from the garnet syenite porphyry of the carbonatite-bearing complex Mushugai-Khuduk, southern Mongolia. Phlogopite, clinopyroxene, albite, potassium feldspar, sphene, wollastonite, magnetite, Ca and Sr sulfates, fluorite, and apatite were identified among the crystalline inclusions. The melt inclusions were homogenized at 1010℃~1080℃ and analyzed on an electron microprobe. Silicate, salt, and combined silicate-salt melt inclusions were found. Silicate melts show considerable variations in SiO2 concentration (56 to 66wt% ), high Na2O + K20 (up to 17wt% ), and elevated Zr, F, and Cl contents. In terms of bulk rock chemistry, the silicate melts are alkali syenites. During thermometric experiments, salt melt inclusions quenched into homogeneous glasses of predominantly sulfate compositions containing no more than 1.3wt% SiO2. These melts are enriched in alkalis, Ba, Sr, P, F, and Cl. The investigation of the silicate and salt melt inclusions in minerals of the garnet syenite porphyries indicate that these rocks were formed under influence of the processes of crystallization differentiation and magma separation into immiscible silicate and salt (sulfate)liquids.  相似文献   

8.
In theory, language teaching today should be entirely monolingual—using target language as the medium of instruction. However, teachers’code switching is common in EFL/ESL classroom which can be 'evidenced along the entire continuum of proficiency’(Brice 2000). This paper is devoted to exploring the theoretical justification for the existence of code switching and the pedagogical purposes for the use of it in EFL classroom, with a hope to raise EFT teachers'awareness of the actual use of code switching in classroom and help them develop an appropriate attitude towards its role in EFL teaching.  相似文献   

9.
张素敏 《科教文汇》2007,(7S):60-61
In theory, language teaclfing today should be entirely monohngual-using target language as the medium of instruction. However, teachers' code switching is common in EFL/ESL classroom which can be 'evidenced along the entire continuum of proficiency' (Brice 2000). This paper is devoted to exploring the theoretical justification for the existence ofcone switching and the pedagogical purposes for the use of it in EFL classroom, with a hope to raise EFT teachers' awareness of the actual use of code switching in classroom and help them develop an appropriate attitude towards its role in EFL teaching.  相似文献   

10.
Objective:PCDD/Fs level in 22 fish samples was investigated in Pearl river Delta area in order that the PCDD/Fs pollution level in common fish can be evaluated. Methods: Dibenzo-p-Dioxins and Dibenzo-Furans was extracted from the sample by Soxhlet extraction, concentrated then purified by column chromatography, carbon column enrichment,. Confirmation and quantitative analysis at ppt(pg/g) level of PCDD/Fs was performed by HRGC/HRMS using multiple ion detection mode(MID). Certified reference material using Proficiency test sample fish muscle test material 0613 that was obtained from Central Science Laboratory(CSL) in Britain. Results: The average of concentration in wet weight is 1.261 ng/kg,, the average total WHO-TEQ for 22 samples is 0.246ng/kg wet weight. Generally, OCDD, 2,3,7,8-TCDF, 1,2,3,4,6,7,8-HpCDD was the main contributors to the total 17 PCDD/Fs detected, average account for 21%,16%,14%, respectively. While 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF, 2,3,7,8-TCDD were main contributors to the total WHO-TEQ, account for 40%,27%, 13% respectively. The total TEQ for 22 fishes ranged from 0.03 ng/kg wet weight to 0.878 ng/kg wet weight. Conclusions: PCDD/Fs level was largely different from sample to sample depending on the sample kinds. The level in the Pearl river Delta area fish samples is not distinct comparing with other countries, but some kind fish level should be paid more attention on it since its higher level. The relationship between source of PCDD/Fs and PCDD/Fs level in fish will be studied deeply in the future.  相似文献   

11.
目的:氦氖激光对葡萄糖溶液、NaCl溶液电导率的影响。方法:以特定的激光强度、经不同的照射时间处理溶液,用电导率仪测定溶液的电导率。结果:氦氖激光照射对葡萄糖溶液电导率的影响,与照射前比较电导率升高,但差异不显著(p>0.05);氦氖激光照射对NaCl溶液电导率的影响,与照射前比较电导率升高,短时间照射,差异不显著(p>0.05),长时间照射(15min以上),差异特别显著 (p<0.01)。结论:氦氖激光对葡萄糖溶液、NaCl溶液的电导率有一定的影响。  相似文献   

12.
薛智韵  陈燕清 《科技广场》2007,20(12):100-102
研究第三方网上支付理论的基础上,对三种典型的电子商务B2B、B2C、C2C的第三方网上支付进行了比较分析,总结了基于B2B、B2C、C2C的第三方网上支付系统模式及其存在的问题,最后规划了第三方协同网上支付的构建模式及其特性。  相似文献   

13.
基于J2ME和J2EE的移动学习平台研究与设计   总被引:1,自引:0,他引:1  
彭政 《科技广场》2010,(6):28-30
随着移动设备性能的不断提高,在移动设备上的应用也越来越广泛,移动学习正是随着移动信息技术发展而产生的一种新兴的学习方式。本文提出了基于J2ME和J2EE技术的移动学习平台的设计方案,这个平台采用J2ME技术作为客户端的实现技术以屏蔽移动设备间的巨大差异性,采用J2EE技术作为服务器端的实现技术以提供高效稳定的服务。  相似文献   

14.
环氧合酶-2在生理状态下多数组织中不表达,当机体受到刺激后可诱导表达,是机体炎症过程的一个重要诱生酶。但近年来国内外大量研究表明其参与肿瘤的发生发展过程,认为可能是肿瘤治疗的一个靶点。现将胃癌与COX-2之间的关系做一综述。  相似文献   

15.
王宝才 《青海科技》1999,6(1):33-34,43
叙述了氯化钠浮选剂1型、2型产品的研制、应用概况及在青海省柴达木盐湖钾资源开发中的作用,并就有关问题提出了看法和建议  相似文献   

16.
以柠檬酸作为胶凝剂,采用溶胶凝胶法制备了一系列CeXZr1-XO2复合氧化物,分别经600℃和900℃焙烧,应用XRD检测,发现均已形成铈锆固溶体。并应用BET、XRD和TPR对其表相、晶相结构和氧化还原性质进行了分析,发现随着固溶体中铈比例的增加,固溶体稳定性降低;其储氧量测定显示铈锆固溶体用作三效催化剂助剂的最佳比例为1:1。经900℃高温焙烧以后,固溶体晶粒增大不明显,表明本方法适合制备高比表面积和高储氧量的铈锆固溶体;TPR还原峰温度降低,推测可能在于柠檬酸络合物完全分解所致。  相似文献   

17.
小议数字“两”、“二”和“2”的用法   总被引:2,自引:0,他引:2  
列举若干实例,从习惯用法、具体含义和特殊用法讨论数字“两”、“二”和“2”的使用方法。  相似文献   

18.
郭威 《科技广场》2010,(5):40-43
学习流系统是运用工作流理论与技术而提出的一种面向学习过程的新型e-Learning学习平台.在介绍了学习流系统相关概念的基础上,提出了一种基于J2EE的学习流系统架构,并对各层进行了详细的设计,最后实现了一个学习流原型系统,较好地解决了目前e-Learning平台对学习过程支持不足的问题.  相似文献   

19.
在纳米SiO2表面引入聚酰胺胺树枝状大分子(PAMAM),再通过原子转移自由基聚合(A-TRP)合成了一种核-壳结构的SiO2-PAMAM-PS,将改性的纳米SiO2添加到PS基体中作为超临界CO2发泡的成核剂。红外光谱(IR)、差示扫描量热仪(DSC)、热重(TG)等结果表明,SiO2表面成功引入了PAMAM,并且接枝上了PS链段。透射电镜(TEM)显示该成核剂具有核-壳结构及其在PS基体中可以较均匀分散。将添加了改性SiO2的PS进行了超临界CO2发泡,利用扫描电镜(SEM)对泡孔结构进行了表征,结果表明:相比于纯发泡PS,成核剂的加入,改善了PS的泡孔结构,使泡孔尺寸显著减小,泡孔密度明显增加。  相似文献   

20.
P2P技术浅析     
文章先将P2P模式与传统的C/S模式相比较,并论述了P2P技术应用的几个领域、技术分类及其存在的一些问题.  相似文献   

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