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锂同位素近年来被认为可以在古环境重建中起到重要作用。锂(Li)作为微量元素,几乎只存在于硅酸盐矿物中,其有两个稳定同位素,分别是6Li(7.5%)和7Li(92.5%),在低温环境可以表现出显著的同位素分馏效应。这些特质预示着Li同位素体系可能会是示踪大陆硅酸盐矿物化学风化过程的有效工具。海洋是自然界Li的重要储库,每公斤海水含有26μM的Li。由于海水混合均匀需要大约1000年的时间,而Li在海水中的滞留时间却长达120万年,所以海
Lithium isotopes have been thought to play an important role in paleoenvironment reconstruction in recent years. Lithium (Li) as a trace element exists almost exclusively in silicate minerals and has two stable isotopes, 6Li (7.5%) and 7Li (92.5%), respectively, which exhibit significant isotopic fractionation effects at low temperatures . These characteristics indicate that the Li isotope system may be an effective tool for tracing chemical weathering of silicate minerals in the mainland. The ocean is an important reservoir of Li in nature with 26 μM of Li per kilogram of seawater. Since seawater mixes uniformly for about 1,000 years, Li’s residence time in seawater is as long as 1.2 million years, so the sea