海底热液喷口环境中，除由高温集中流喷发形成的硫化物烟囱体之外，还存在着分布范围更为广泛、由低温弥散流喷发形成的富Fe-Si热液沉淀物。这些低温热液沉淀物环境是地球上最具生产力的生态系统之一，因其所具有的特殊环境配置，成为开展矿物学、地球化学、微生物学及其相互作用研究的绝佳载体和天然实验室。本课题以广泛分布于海底热液喷口周围的富Fe-Si低温热液沉淀物为研究对象，运用多种技术和研究方法，揭示和比较不同类型富Fe-Si低温热液沉淀物的矿物、地球化学和显微结构等方面的特征，追踪和分析参与微生物矿化的微生物菌群，确定不同类型富Fe-Si低温热液沉淀物的微生物矿化类型。同时，结合实验室的模拟，建立不同类型富Fe-Si低温热液沉淀物的微生物矿化模型。在上述结果的基础上，依赖于地化参数和具有特殊生态功能的微生物类群对热液沉淀物中地球化学体系的阐述，最终建立不同类型富Fe-Si低温热液沉淀物的形成机制。

In the seafloor hydrothermal vent environment, along with sulfide chimneys formed by the eruption of high-temperature focus flow, there also exist more widely distributed Fe-Si-rich hydrothermal precipitates formed by eruption of low-temperature diffuse flow. These low-temperature hydrothermal precipitate environments are one of the most productive ecosystems on Earth. Due of their special environmental configuration, they have become excellent carriers and natural laboratories to carry out mineralogical, geochemical and microbiological studies and explore the interactions between them. In this study we will employ a variety of techniques and methods to study the low-temperature Fe-Si-rich hydrothermal precipitates which are widely spread around the seafloor hydrothermal vents. Further, we will illustrate and compare the features of different types of low-temperature Fe-Si-rich hydrothermal precipitates from aspects of mineralogy, geochemistry and ultrastructures. Additionally, we aim to track and analyze the microbial groups involved in microbial mineralization and determine the different types of such mineralization associated with various low-temperature Fe-Si-rich precipitates. Finally, combined with laboratory simulation, we will build different microbial mineralization models of low-temperature Fe-Si-rich hydrothermal precipitates. Based on the results above，we can eventually establish the formation mechanisms of different types of low-temperature Fe-Si-rich hydrothermal precipitates relying on the elaboration of hydrothermal precipitate geochemical system deciphered by geochemical parameters and microbial groups with special ecological functions.