沉积参数控制着海相黄铁矿硫同位素组成，这一成果由以色列魏茨曼科学研究所 I. Halevy 研究小组经过不懈努力而取得。2023年11月24日，《科学》期刊发表了这一成果。

研究人员利用沉积物成岩作用模型，结合全球沉积参数数据集，发现现代海洋沉积物 δ ³⁴S_pyr(约 100 per mil)的大范围来源于硫酸盐的相对扩散、埋藏和微生物还原速率的地理模式。相比之下，微生物硫同位素分馏仍然较大且相对均匀。在地球历史上，海水中硫酸盐和氧浓度的增加对硫酸盐和硫化物迁移和反应的影响，可以解释硫酸盐和黄铁矿之间 δ ³⁴S 偏移的相应增加。更细微的变化可能与与海平面波动和超大陆旋回有关的沉积环境变化有关。

据介绍，碳、氧和硫循环的重建主要依赖于沉积黄铁矿硫同位素组成(δ ³⁴S_pyr)。

附：英文原文

Title: Sedimentary parameters control the sulfur isotope composition of marine pyrite

Author: I. Halevy, D. A. Fike, V. Pasquier, R. N. Bryant, C. B. Wenk, A. V. Turchyn, D. T. Johnston, G. E. Claypool

Issue&Volume: 2023-11-24

Abstract: Reconstructions of coupled carbon, oxygen, and sulfur cycles rely heavily on sedimentary pyrite sulfur isotope compositions (δ ³⁴S_pyr). With a model of sediment diagenesis, paired with global datasets of sedimentary parameters, we show that the wide range of δ ³⁴S_pyr (~100 per mil) in modern marine sediments arises from geographic patterns in the relative rates of diffusion, burial, and microbial reduction of sulfate. By contrast, the microbial sulfur isotope fractionation remains large and relatively uniform. Over Earth history, the effect of increasing seawater sulfate and oxygen concentrations on sulfate and sulfide transport and reaction may explain the corresponding increase observed in the δ ³⁴S offset between sulfate and pyrite. More subtle variations may be related to changes in depositional environments associated with sea level fluctuations and supercontinent cycles.

DOI: adh1215

Source: https://www.science.org/doi/10.1126/science.adh1215