Using Geochemical Tracer Research The Source Of Metal In Geogas

At present, the focus of mineral exploration has shifted to the concealed area. It is urgent that find a exploration method for concealed area. And geogas by the Swedish scientist K. Kristiansson and L. Malmqvist of the twentieth century to the early eighties, and is a promising method of geochemical prospecting. Since the end of the 1980s’the introduction to China since both experimental and production has made great progress, especially in the application of liquid collector. And geogas has gradually been accepted, but the mechanism study is still insufficient, as well as the blank control, means of analysis and the choice of geogas and so on are restricted to the factors that promote geogas.Blank in HR-ICP-MS and low gas content in the background samples, Q-ICP-MS abnormal samples, higher accuracy, to fulfil the requirements of tracer studies.The adoption of international standards for conditions of optimization and quality control samples, HR-ICP-MS and Q-ICP-MS can be achieved in gas samples measured lead isotope ratios.As a collector for trapping geogas water is weak, 5% nitric acid and 3% aqua regia are better than water. Because nitric acid is the commonly used medium for ICP-MS, so 3% nitric acid is the ideal choice. The results also show that the need to choose the pressure reducer with the different collectors and the nature.At the same time, the author analyze the lead isotopes, trace elements and REE of the rock (ore) and geogas in North Qilian. The results showed that lead isotope composition of geological body is different.Background samples deviate from all known geological body, indicating its sources of lead is non-geologic(blank and air); anomaly geogas lead isotopic composition is obviously different from the background, and with the ore is very close to or even coincidence show that the lead of abnormal geogas has the same sources or similar homology with ore. The result of trace elements show that abnormal geogas and the background is different, but closer to the ore. At the same time, the study of REE found that abnormal geogas is different from the background, but very similar to the ore. Therefore, lead isotope, trace elements and REE all can be used to trace the source of geogas. However, to obtain more reliable data, we need to ameliorate methods to improve the REE content of gas samples especially background.