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黄土和红粘土为风尘物质,其Sr同位素的研究较为深入,其它风尘物质还包括深海沉积物和冰芯中的粉尘物质,以及现代风尘物质,它们的Sr同位素亦有较多研究。Sr主要以分散形式存在于风尘物质含钙矿物中。风尘物质中碳酸盐矿物Sr同位素值低,硅酸盐矿物高。风尘物质Sr同位素示踪研究一般采用硅酸盐组分,但不同粒级组分Sr同位素组成不同,<2μm组分具有最高值,它影响全岩Sr同位素组成;采用固定粒级具有很好的示踪效果。利用碳酸盐Sr同位素进行风尘物源示踪,表明中国北方沙漠碳酸盐具有不同的Sr同位素组成,它受控于地质背景和化学风化程度。
Loess and red clay are dusty dusts, and their Sr isotopes are well studied. Other dusty dusts also include dusts from deep-sea sediments and ice cores, as well as modern dusty dusts. Their Sr isotopes are also studied more. Sr is mainly dispersed in the dust-containing calcium minerals. Sediment matter carbonate minerals Sr isotope value is low, silicate minerals high. The Sr isotope tracer of dust and dust material generally uses silicate components, but different grain fractions have different Sr isotopic composition, <2μm fraction has the highest value, which affects the whole rock Sr isotope composition; Tracing effect. Carbonate Sr isotopes are used to trace the source of dust and dust, indicating that the desert carbonate in northern China has different Sr isotopic composition, which is controlled by the geological background and the degree of chemical weathering.