中文摘要:建立了硅同位素测量方法，获得了比前人更高的测量精度。分析了52个地质样品，探讨了硅同位素地质应用的前景。
Abstract:A SiF4 preparation line as shown in Fig.1 was assembled and the analytic method of silicon isotopes was developed in this study. In order to improve the purity of produced SiF4, two steps were added to the ordinary procedure of SiF4 preparation. One is cleaning of the impurities, such as SiF4, SF6 and CF4, existent in BrF5 reagent beforehand by using dry ice-aceton freezing separation technique. The other is cleaning away the trace amount of BrF5 and other active F-bearing residue, which may exist in produced SiF4 even after several steps of freezing separation, by reacting them with Zn particles in a heated copper tube. By using these methods much purer SiF4 gas can be obtained. The δ30Si values of SiF4 we are analysed in a Mat-251 EM mass-spectrometer with multiply collectors. The NBS-28 standard, a working standard of quartz in our laboratory, a SiO2 sample chemically prepared from diatom and a meteorite were analysed repeatedly and the standard deviations of δ30Si values obtained for these samples were±0.03—0.1‰, which is better than those reported by Douthitt(1982). Theδ30Si values for 52 samples of rocks and minerals were reported in Table 1. The fractionations of silicon isotopes in igneous rocks and hydrother-real minerals are quite small, and are the same as those reported in Douthitt(1982). However, clay minerals show much wider range of δ30Si variation (0.1一-112‰)than the range reported in Douthitt(1982). Our resltlts show also the possibility of using δ30Si values to discriminate clays of different geneses. Besides, the δ30Si values of biological silicon sediments also show some interesting variations.
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丁悌平，万德芳，李金城，蒋少涌，宋鹤彬，李延河，刘志坚.1988.硅同位素测量方法及其地质应用[J].矿床地质,7(4):90~96.1988.The analytic method of silicon isotopes and its geological application[J].Mineral Deposits7(4):90~96
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