海陆相蒸发岩硫同位素值变化和地球化学应用

The Variation of Sulfur Isotope in Marine-continental Evaporites and Its Geochemical Applications

硫同位素作为一种稳定的同位素,几乎遍布各种自然环境,出现于地质上所能跨越的所有温度范围。自然界中,不同环境下δ^(34)S值的差别可达180‰。研究表明,蒸发沉积硫酸盐的δ^(34)S值可以代表相应水体的δ^(34)S值,通过研究蒸发岩中的δ34S值,结合其它指标,可判断沉积环境,示踪成矿物质来源,研究成矿作用过程,为重建古地理古环境提供依据。在前人研究基础上总结了硫同位素分馏的影响因素及其在地球化学方面的应用;分析了陆相盆地蒸发咸化过程中水体δ^(34)S值的变化特征;对比研究了部分海陆相盆地硫酸盐δ^(34)S值特征,并指出对陆相盆地,不同类型的水体中δ^(34)S值变化趋势仍需进一步研究。

Sulfur, as the stable isotope, almost shows up in all natural environments and the geological temperature range. The variation range of sulfur isotope reaches 160‰. By studying the sulfur isotope in the evaporites, many researches acknowledge the evaporites bear the similar sulfur isotope values with the water bodies, so we can judge the sources of evaporite deposits and the paleoenvironment to reconstruct the paleogeography combining with other indicators. In this paper, on the basis of the previous research, we summarized the influence factors of the sulfur isotope; the variation characteristics of the marine evaporites＇ sulfur isotope along with the time and its geochemical applications ; the sulfur isotope characteristics of different water types during the evaporating process ; the differences of the sulfur isotope in some marine and continental basins. In the con- tinental basin, the variations of sulfur isotope along with the type of water bodies need further research.