稳定同位素地球化学研究新况

近年来稳定同位素地球化学进展显著。同位素测试方面的主要进展表现为：①离子探针质谱及激光制样系统的迅速发展和在同位素分析中广泛应用；②同位素测量仪器的自动化和电脑化；③分析方法和结果标准化；④新的同位素分析方法的开拓。同位素分馏机制方面最突出的进展是对与质量无关的同位素分馏的研究。已发现这种分馏在大气化学反应中和前太阳系阶段起重要作用。同时对热力学和动力学同位素分馏研究正进一步系统化。同位素应用方面，地球表面圈层研究受到更多注意。与资源与环境问题直接相关的研究更受到特别重视。对硼、硅、氯和锂等同位素新方法的地质应用也进展突出。

ON PRESENT STATE OF STABLE ISOTOPE GEOCHEMISTRY

During recent years,remarkable progresses have been made in stable isotopegeochemistry.In the aspect of stable isotope analysis,the major improvements are follow-ing:a)micro-analysis techniques,such as ion probe mass-spectrometer and laser probesample extraction systems, are rapidly developed and widely used in stable isotope analy-ses; b)automation and computerization of instruments for isotope measurements; c)stan-dardization of analytic,methods and results;and d)development of new method of isotope-analysis.On isotopic fractionation mechanisms, the most attractive progress is made in thestudy of mass independent isotopic fractionation, which has been found in several chemicalprocesses in atmosphere as well as in the processes of presolar stage.Meanwhile,thestudies on thermodynamic and kinetic isotopic fractionations become more systematic.As to the application of isotopic studies,much attention is put on the investigations ofsurface layers of the Earth.Studies related directly to environmental and resource prob-lems are specially emphasized.Progress has been also made on the application of newly de-veloped methods, such as B,Si,Cl and Li isotope analyses,to various geological prob-lems.