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1.
Abundant melt-and fluid inclusions occur in corundum megacrysts of alkaline basalt from the Changle area, Shandong province, eastern China. One type of melt inclusions, i.e. muhiphase melt inclusions （glass ＋ bubbles ＋ daughter minerals） were identified , which occur along growth zones of host corundum megacrysts. Microthermometry and laser Raman microprobe analysis were performed on the melt inclusions. The bubbles within the melt inclusions are confirmed to be CO2-rich phase and the daughter minerals are probably silicates, such as augite and okenite. The results of high temperature homogenization experiment strongly suggest that two immiscible melts, i.e. a H2O-and CO2-rich melt and an anhydrous and CO2-poor melt were trapped by melt inclusions in corundum megacryst. 相似文献
2.
IrinaA.Andreeva Vyacheslav I.Kovalenko Vladimir B.Naumov 《中国科技期刊研究》2007,23(1):73-82
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
3.
Mantle xenoliths are common in the Cenozoic basalts of the Changbaishan District, Jilin Province, China. Sulfide assemblages in mantle minerals can be divided into three types： isolated sulfide grains, sulfide-meh inclusions and filling sulfides in fractures. Sulfide-inch inclusions occur as single-phase sulfides, sulfide-silicate melt, and CO2-sulfide-silicate melt inclusions. Isolated sulfide grains are mainly composed of pyrrhotite, but cubanite was found occasionally. Sulfide-inch inclusions are mainly composed of pentlandite and MSS, with small amounts of chalcopyrite and talnakhite. The calculated distribution coefficient KD3 for lherzolite are similar to that of mean experimental value. The bulk sulfides in lherzolite were in equilibrium with the enclosing minerals, indicating immiscible sulfide melts captured in partial melting of upper mantle. Sulfide in fractures has higher Ni/Fe and （Fe ＋ Ni）/S than those of sulfide melt inclusions. They might represent later metasomatizing fluids in the mantle. Ni/Fe and （ Fe ＋ Ni ）/S increase from isolated grains, sulfide inclusions to sulfides in fractures. These changes were not only affected by temperature and pressure, but by geochemistry of Ni, Fe and Cu, and sulfur fugacity as well. 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.
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
6.
Kingsley Burlinson 《中国科技期刊研究》2007,23(1):65-71
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.
Halite precipitation with water and air temperature was observed in detail, and homogenization temperature of fluid inclusions in halite formed in ancient and modem Chaka Salt Lake was studied. Halite precipitates mainly in August every year and largely precipitates between 13 and 15pm at one day when water temperatures reach 20℃ but can seldom reach 30℃. Homogenization temperatures of fluid inclusions in halite formed in Chaka Salt Lake range from 14℃ to 38℃ with an average of 23.7℃. The number of inclusions appears an obvious peak value at homogenization temperatures between 18 - 25℃, which probably represent the water temperature in which halite mainly precipitates when water temperatures reach 20℃. Therefore, homogenization temperatures of fluid inclusions in halite formed in Chaka Salt Lake can wall reflect the water temperature. 相似文献
8.
Well S provides a good opportunity to investigate the petroleum filling history in Tazhong North Slope. Petrographic investigations suggest that bitumen, oil, and petroleum inclusions coexist in Silurian sandstones from well S, reflecting a complicated reservoir filling history in the study area. Integration of organic geochemistry and fluid inclusion analysis shows that the Silurian reservoir has experienced three episodes of petroleum charge, that is from the late Silurian to the early Devonian, the early-middle Triassic and the Paleogene, respectively. The present-day reservoir fluids in the Silurian are the mixtures generated in multiple （ at least two） episodes of petroleum charge. The oil charging into Silurian resevior in the early period had experienced considerable degradation, and was mixed with later non-degraded oil. 相似文献
9.
《中国科学院院刊(英文版)》2008,22(2)
Horseflies are a blood-feeding arthropod, notorious as a common pest of animals and sometimes of humans. While a target of the biological control in green farming and animal husbandry, dried bodies of the females, known as mangchong, are used in traditional Chinese medicine (TCM) to treat cardiovascular diseases. Although the unique drug is believed to contain various bioactive substances, little has been known about its biochemical functions in the secretion of the insect's salivary glands and, in parti... 相似文献
10.
Rainer Thomas Paul Davidson 《中国科技期刊研究》2007,23(1):15-20
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
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