Formation, Stability and Reactivity of Metastable Sulfur Oxyanions in Hydrothermal Solutions

9407099本研究的目的是通过实验研究和野外工作来评估硫氧阴离子在水热体系中可能起到的作用。由于对这些硫磺物种的稳定性知之甚少，PI在该计划的第一阶段进行了实验，以研究硫代硫酸盐的稳定性。在这个供资周期中，私营部门建议将实验工作的重点放在硫代硫酸盐的形成上。硫代硫酸盐的形成有两条途径：1)在矿物表面和金属离子存在下的H_2S-SO_4平衡；2)以含Fe(III)矿物为氧化剂的H_2S氧化，温度最高可达250℃。第三个主要途径是O2氧化H_2S，这是我们野外工作的重点。黄石公园将被用作天然实验室，以补充石溪的实验研究。这项实地工作将使我们做好准备，迎接对深部热液进行采样的挑战，这是一项长期目标。

9407099 Schoonen The objective of the research is to evaluate through experimental studies and field work the role sulfur oxyanions may play in hydrothermal systems. Because little is known about the stability of these sulfur species, the PI has conducted experiments in the first stage of this program to study the stability of thiosulfate. For this funding cycle, the PI proposes to focus the experimental work on the formation of thiosulfate. Two pathways for thiosulfate formation: 1) H2S-SO4 equilibration in the presence of mineral surfaces and metal ions, and 2) H2S oxidation with FE(III) bearing minerals as oxidants will be studied to temperatures up to 250oC. A third major pathway, H2S oxidation by O2, is the focus of our field work. Yellowstone will be used as a natural lab to complement the experimental studies at Stony Brook. This field work will prepare us for the challenges of sampling deep hydrothermal fluids which is a long-term objective.