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热力学计算及在实验室进行的实验都指明了硫化羰基(COS)作为寻找覆盖层下隐伏硫化物矿床一种气相指标的潜在价值。因此,已经发展了一些测定覆盖物中COS的简便的取样、分析技术。在气候温湿地区,土样取自植物根系以下;在干旱和半干旱地区,样品采自地表微层,分析步骤包括对小于150μm粒度的覆盖物中的COS进行选择性热解吸,然后迅速用气相色谱方法进行定量测定。在美国西南部的交代型Cu(Zn)矿和斑岩Cu矿、沙特阿拉伯的变质沉积型Cu-Zn矿、南非的火山沉积型多金属硫化物矿及爱尔兰的层控Pb-Zn矿等矿床的上方进行了COS地表分散模式的野外研究,现在此描述。这些矿床均被不同类型、不同厚度的覆盖物所覆盖。在这些矿床上方的覆盖层中均出现COS的异常浓度,这些异常一般具有一定的但令人满意的衬度。在有些例证中异常不连续,或呈补钉状。结果表明,COS可以用作寻找各种地质地理条件下隐伏矿床的指标。它甚至可以识别位于90多米厚运积物之下的矿化所引起的异常。
Thermodynamic calculations and experiments conducted in the laboratory have indicated the potential value of carbonyl sulfide (COS) as a gas phase index for finding buried sulfide deposits under cover. Therefore, some simple sampling and analysis techniques for determining COS in cover have been developed. In warm and humid climates, the soil samples are taken from the roots of the plant; in arid and semi-arid areas the samples are taken from the surface microlayer and the analysis step includes selective thermal desorption of COS in a cover of less than 150 μm particle size followed by rapid Gas chromatography method for quantitative determination. In the southwestern United States, the metasedimentary Cu (Zn) and porphyry Cu deposits, the metamorphic sedimentary Cu-Zn deposits in Saudi Arabia, the volcanic sedimentary polymetallic sulphide deposits in South Africa and the stratiform Pb-Zn ore deposits in Ireland The field study of the COS surface dispersion model was carried out at the top, as described now. These deposits are covered by different types and thicknesses of cover. Abnormal concentrations of COS occur in the overburden of these deposits, and these anomalies generally have a certain but satisfactory contrast. In some cases the anomalies are discontinuous or patchy. The results show that COS can be used as an indicator to find hidden deposits under various geological and geologic conditions. It even identifies anomalies caused by mineralization beneath more than 90 meters of sediment.