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31.
研制了检测盐湖和盐田卤水温度、密度和水位的传惑器,并建立了盐湖高浓度卤水中钾离子含量的直接自动测定方法。为了使传感器在青藏高原盐湖的恶劣环境中长期稳定工作,并防止探头结盐与腐蚀,采取了一系列技术措施。这些传感器用于察尔汗盐湖卤水动态自动观测系统中,取得了满意的效果。 相似文献
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M. Solomon F. Tornos R. R. Large J. N. P. Badham R. A. Both Khin Zaw 《Ore Geology Reviews》2004,25(3-4):259-283
Eight Zn–Pb–Cu massive sulphide deposits that appear to have formed on the sea floor (seven in Spain, one in Tasmania) are believed to have been precipitated in brine pools, based on the salinities and temperatures of fluid inclusions in underlying stockworks. Comparing the geological features of these deposits with those of the Zn–Pb–Cu massive sulphide ores of the Hokuroku Basin, Japan, which have formed as mounds from buoyant fluids of low salinity, shows that brine pool deposits have: (1) potentially very large size and tonnage, and high aspect ratio, (2) higher Zn/Cu and Fe/Cu values, (3) no evidence of chimneys, (4) relatively abundant framboidal pyrite and primary mineral banding, (5) reduced mineral assemblages (pyrite-arsenopyrite/pyrrhotite), and minor or rare barite in the massive sulphide, (6) associated stratiform and/or vein carbonates, (7) relatively unimportant zone refining, (8) lack of vertical variation in sphalerite and sulphur isotopic compositions, and (9) evidence of local bacterial sulphate reduction. Application of these criteria to the Rosebery deposit in Tasmania, for which there are no fluid inclusion data, leads to the conclusion that the southern section was deposited as separate lenses in a brine-filled basin or basins. Other potential candidates include Brunswick no. 12 and Heath Steele (Canada), Woodlawn and Captains Flat (New South Wales), Hercules and Que River (Tasmania), and Tharsis and the orebodies at Aljustrel (Spain and Portugal). Recently published fluid inclusion data for Gacun (China) and Mount Chalmers (Queensland) suggest that not all ores deposited from highly saline fluids have reduced mineral assemblages. 相似文献
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巴彦浩特盆地自中生代至今一直是一自流水的构造盆地,其具有成钾的构造、气候、水文以及古盐释放等有利条件。该区存在着高灵敏度航空伽玛能谱测量发现的现代高钾异常区,由区内已知盐类矿床(点)的存在及铀、钍元素的地球化学的分布特点知,高钾异常与含钾的盐类物质密切相关。高钾异常的分布及其形态特征表明了本区可能存在较深层卤水,并高钾异常的形成是由于沙丘带与盐湖带问的风积作用、两者间的内循环作用以及两者对较深层卤水存在的蒸发作用的共同结果。根据统计及估算,本区可称之为一具一定远景储量的钾盐远景区。它反映了钾盐富集的一种不同形式,实则体现了构造、气候、水文、盐湖、沙漠五者的密切相关和极好的统一,是沙丘(山)型钾盐成矿模式的代表。 相似文献
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E. Gonzlez-Partida A. Carrillo-Chvez J. O. W. Grimmer J. Pironon J. Mutterer G. Levresse 《Ore Geology Reviews》2003,23(3-4):107-124
Petroleum and aqueous fluid inclusions from the Encantada–Buenavista fluorite mineralized zone in northern Mexico were analyzed by microthermometry, UV fluorescence, Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR) and Confocal Scanning Laser Microscopy (CSLM) to evaluate the geochemical evolution of the mineralizing fluids. Two-phase (petroleum or brine+vapor) and three-phase (petroleum+brine+vapor) inclusions are described. Aqueous and petroleum-rich inclusions commonly occur in the same plane. Vapor-decrepitated and stretched fluid inclusions are present. A low-salinity methane-saturated fluid and a high salinity-fluid with highly variable methane contents are recognized. H2S is not quantified but is always detected in close association with methane. Petroleum inclusions are of two types: a low methane petroleum fluid (20 mol%) with low Th (60 °C) and a petroleum fluid with a methane of content near 30 mol% and a Th of 90 °C.Pressure and temperature diagrams for the aqueous and petroleum inclusions show three main intersects that allow P–T–X reconstruction of fluid evolution at La Encantada–Buenavista. A CH4- and H2S-rich low-salinity brine was mixed with oil that migrated under hydrostatic conditions with a thermal gradient of 70 °C/km. The arrival and mixing of a high-salinity aqueous fluid produced overpressure to 300 bars. A return to hydrostatic conditions was accompanied by an increase in the thermal gradient.The brine related to the fluorite orebodies appears to have a genetic relationship with the brines reported from the Jurassic petroleum basins located west of the fluorite bodies and similarities with reported fluids from Mississippi Valley type deposits. It is interpreted that the fluorine-rich fluids migrated toward the platform margins during the mid-Tertiary (30 to 32 Ma) using extension zones related to Basin and Range tectonism. Mixing of two different brines was responsible for precipitation and mineralization. Heat from magmas, related to tectonic extension, caused decrepitation and changes in the shape of fluid inclusions near the contact zones. 相似文献
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矿床产于中寒武田蓬组地层中,受地层、沉积岩相、变质岩相控制。围岩蚀变为黄铁矿化、锰矿化、碳酸盐化、硅化。矿床成因为海底含矿热卤水喷流沉积型。 相似文献
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盐湖卤水由于富集了大量的复杂有机物,而具有浓厚的颜色,脱除这些有色物质,既可以减少卤水对生产设备的危害,又可以提高产品的色度,有利于卤水的综合开发利用,是卤水精制的主要内容。采用不同极性的有机溶剂正己烷和氯仿分别对盐湖卤水中的有机物进行萃取分离,浓缩处理,通过GC-MS联用技术对萃取后的有机提取物进行分离和结构鉴定。结果表明,盐湖卤水中主要含有一些饱和脂肪烃、芳香烃、醇类、酯类、酮类和醚类有机物,为卤水脱色的研究提供了一定的线索和指导。 相似文献
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