The genetic relationship between ultramafic-hosted massive sulfides and their host rocks: petrological, geochemical and isotopic investigations of hydrothermal systems along the Mid-Atlantic Ridge between 14°45`N and 15°05`N

在14°45´N和15°05´N之间缓慢扩张的大西洋中脊，热液系统（沉淀、喷口流体和喷口动物群）及其超镁质寄主岩之间的成因关系是本合作项目的重点。主要的科学问题是热液循环和浸出是否发生在超基性岩石或玄武岩或辉长岩岩性中，这些岩性也存在于该地区。原生地幔物质的岩石学特征、部分熔融程度以及原生硫化物和次生硫化物的矿物学和化学组成是了解烃源岩为热液系统提供元素作用（“烃源岩控制”）的关键。在海底热液沉淀物的矿物学、地球化学和同位素组成上确定烃源岩（包括PGEs和os同位素）的指纹将有助于实现这一目标，并为合作研究小组的研究提供重要信息，这些研究小组专注于流体化学、热液系统随时间的演化以及矿物表面的微生物过程。该项目的样本将在“流星”巡航期间收集。

The genetic relationship between hydrothermal systems (precipitates, vent fluids, and vent fauna) and their ultramafic host rocks along the slow-spreading mid-Atlantic ridge between 14°45´N and 15°05´N is the focus of this cooperative project. The main scientific question is whether hydrothermal circulation and leaching has taken place in ultramafic rocks or in basaltic or gabbroic lithologies that are also present in the area. The petrology of the primary mantle material, the degree of partial melting, and the mineralogical and chemical composition of both primary and secondary sulfides are keys to understand the role of the source rocks in providing elements to the hydrothermal system ("source rock control"). The determination of fingerprints of the source rock (including PGEs and Os-isotopes) on the mineralogical, geochemical, and isotopic composition of the hydrothermal precipitates at the seafloor will add to this goal and also provide vital information for the studies of cooperating research groups that focus on fluid chemistry, evolution of the hydrothermal systems over time, and microbial processes at mineral surfaces. The samples for this project will be collected during "Meteor"-cruises.