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1.
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   

2.
水对乙醇溶液荧光光谱和拉曼光谱的影响研究   总被引:1,自引:0,他引:1  
液相荧光光谱和拉曼光谱的检测是常用而灵敏的检测技术,水作为常用溶剂对荧光光谱和拉曼光谱的影响直接影响检测的灵敏度.本文通过对纯水,无水乙醇及不同浓度乙醇溶液的荧光光谱和拉曼光谱进行理论和实验分析,研究水时乙醇溶液光谱的影响.结果表明,纯水在可见激发光激发下不产生荧光,对乙醇溶液的荧光光谱和拉曼光谱不产生影响;纯水产生拉曼光谱,对用拉曼光谱法检测乙醇浓度有影响.  相似文献   

3.
<正>2010年3月18日出版的英国Nature(2010,464,392—395)发表了厦门大学化学化工学院田中群教授研究组与其合作者在壳层隔绝纳米粒子增强拉曼光谱方法方面的重要研究进展。该研究组与美国佐治亚理工学院王中林研究组  相似文献   

4.
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   

5.
The strong spatial confinement of a nanocavity plasmonic field has made it possible to visualize the inner structure of a single molecule and even to distinguish its vibrational modes in real space. With such ever-improved spatial resolution, it is anticipated that full vibrational imaging of a molecule could be achieved to reveal molecular structural details. Here we demonstrate full Raman images of individual vibrational modes at the ångström level for a single Mg-porphine molecule, revealing distinct characteristics of each vibrational mode in real space. Furthermore, by exploiting the underlying interference effect and Raman fingerprint database, we propose a new methodology for structural determination, which we have called ‘scanning Raman picoscopy’, to show how such ultrahigh-resolution spectromicroscopic vibrational images can be used to visually assemble the chemical structure of a single molecule through a simple Lego-like building process.  相似文献   

6.
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   

7.
对瑶岗仙石英脉型钨矿床的石英、萤石和夕卡岩型钨矿床中石榴石流体包裹体的岩相学特征研究表明,与成矿有关的包裹体主要有三类:富液相、富气相和含子晶的多相包裹体。脉型钨矿床中石英包裹体均一温度范围为180℃-300℃,盐度O.88—6.45wt%NaCleqv;矽卡岩型钨矿床中石榴石包裹体的均一温度范围为190℃~300℃,盐度0.1~8.95wt%NaCleqv;成矿溶液的密度为0.81~0.89g/cm^3.表明形成这两种类型矿床的成矿流体均属于中温、低盐度、低密度的流体;成矿压力为120~160MPa,成矿深度约为7—9km,因此该矿床是在中高压力、中深成条件下形成的。激光拉曼探针分析表明,石英中包裹体的气相成分比石榴石中的更富含CH4、CO2和H2O等挥发份,说明流体是一种介于岩浆与热液之间的过渡性流体,具有上部偏液、下部偏浆的特点。由于该区自燕山期以来软流圈上隆,岩石圈经历了强烈的伸展、减薄作用和壳幔相互作用,而C-H还原性组分的增加,指示流体很可能来自于深部的地幔过渡带或者软流圈。  相似文献   

8.
<正>In 1930,just two years ater his report on‘A New Type of Secondary Radiation’from the scatering of focused beams of sunlight in liquid benzene[1]Sir CV Raman received the Nobel Prize in Physics‘for his work on the scatering of light and for the discovery of the efect named after him’.his great honor was awarded so soon because the scientiic community immediately recognized that the Raman efect could be developed into a powerful ingerprint vibrational spectroscopy  相似文献   

9.
10.
青藏高原水资源的保护与利用   总被引:5,自引:0,他引:5  
本文通过对青藏高原河流、湖泊、冰川和湿地的水资源含量、分布,以及水资源开发利用现状的分析,指出青藏高原水资源丰富,但同时存在时空分布过于集中、开发条件差、利用难度大等开发劣势,且面临着河湖干涸和水污染等严峻的生态与环境问题.为实现青藏高原水资源的永续利用,提出开发利用高原水资源必须注重保护原生生态系统;最大限度地开发水资源的有用性,提高用水效率;并针对高原核心区、高原周边地区和高原延伸区各自不同的特点施以不同的利用和保护措施.  相似文献   

11.
近年来,随着新疆社会经济不断发展,大面积土地开发与水资源有限、粮食安全问题与种植业经济利益驱动性之间的矛盾加剧,水资源合理配置及种植业结构优化的重要性日益凸显。本文以新疆库尔勒市为例,根据其水资源开发利用特点,综合考虑经济、生态、粮食安全等因素,结合种植业发展重点,提出四个发展方案,建立水资源优化配置模型,利用数据包络分析方法进行投入产出效率评价。结果表明:高自给率低投资的种植业发展方案,既能满足一定的粮食自给率要求,又不过多增加节水灌溉投资费用,其投入产出效率最高,可视为种植业发展规划的基础方案。根据该方案,2020年种植业总面积应控制在84000hm2左右,粮食、经济作物、果园种植比例为26∶56∶18。从目前情况来讲,应通过增加粮食作物种植面积、发展果园节水灌溉、减少果园大田种植等提高粮食自给率和经济效益,同时节水灌溉改造费不应超过种植业总产值的3%,以免造成投资过剩。  相似文献   

12.
水环境安全是一个备受关注的全球性问题,各国都在积极进行调查与防治。由于岩溶水的变化特点,必须对其指标进行现场测定,并在其调查、研究中引入新技术、先进测试设备。同时,仪器设备管理应该更加科学化、规范化,保证调查研究的高效性、数据准确性,并节约成本。  相似文献   

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