Stable isotope fractionation of chlorine during the precipitation of single chloride minerals
Stable isotope fractionation of chlorine during the precipitation of single chloride minerals
复制标题
单氯化物矿物沉淀过程中氯的稳定同位素分馏
DOI：
10.1016/j.apgeochem.2014.06.005
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发表时间：
2014-08-01
影响因子：
3.4
通讯作者：
He, Maoyong
中科院分区：
文献类型：
--
作者：
Luo, Chongguang;Xiao, Yingkai;He, Maoyong
为了更好地了解盐水演化过程中氯同位素的变化，设计了实验来确定在28 +/- 2 ℃下含有NaCl、KCl和MgCl 2中心点6 H（2）O的溶液蒸发过程中氯同位素组成（δ Cl-37值）的变化。在清洁环境中进行三个蒸发实验。在蒸发过程中收集沉淀物和盐水样品，并使用基于Cs2 Cl+离子测量的改进的热电离质谱法程序确定样品的氯同位素比。其结果如下：三种溶液的平均分馏因子分别为α（Na）= 1.00055、α（K）= 1.00025和α（Mg）= 1.00012，其中α（Na）、α（K）和α（Mg）是盐（NaCl、KCl和MgCl 2中心点6 H（2）O）与饱和溶液之间的分馏因子。结果表明，在单一氯化物矿物沉淀过程中，沉淀物和共存卤水样品的δ Cl-37值均降低。对于不同的单一氯化物溶液，剩余盐水是Cl-35储层。计算了海水蒸发过程中新的氯同位素演化曲线。结果表明，在石盐的初次沉淀阶段，δ Cl-37不断下降，最重要的是，在镁盐开始沉淀的最后阶段，δ Cl-37仍呈下降趋势。(C)2014爱思唯尔有限公司版权所有。
In order to better understand chlorine isotopic variations during brine evolution, experiments were designed to determine the changes in the chlorine isotope composition (delta Cl-37 value) during evaporations of solutions containing NaCl, KCl and MgCl2 center dot 6H(2)O at 28 +/- 2 degrees C. Three evaporation experiments were conducted in a clean environment. The precipitate and brine samples were collected during the evaporation, and the chlorine isotopic ratios of the samples were determined using an improved thermal ionisation mass spectrometry procedure based on Cs2Cl+ ion measurement. The results are as follows: the mean fractionation factors of the three solutions are alpha(Na) = 1.00055, alpha(K) = 1.00025, and alpha(Mg) = 1.00012, respectively, where alpha(Na), alpha(K) and alpha(Mg) are the fractionation factors between salts (NaCl, KCl and MgCl2 center dot 6H(2)O) and saturated solutions. The results showed that the delta Cl-37 values of precipitate and coexisting brine samples decrease during the precipitation of single chloride minerals. The residual brine was a Cl-35 reservoir for different single chloride solutions. New chlorine isotopic evolution curve during seawater evaporation were also calculated. The results indicated that during the primary precipitation stage of halite, delta Cl-37 decreased continuously, and the most important thing is that this trend continues during the final stages when Mg-salts begin to precipitate. (C) 2014 Elsevier Ltd. All rights reserved.