Tectono-magmatic controls on hydrothermal activity at the Mid-Atlantic Ridge vent fields Logatchev and 5°S

拟议的工作旨在了解缓慢扩张海脊的构造岩浆过程与热液喷发的起源和性质之间的关系。特别是，我们将测试，如果离轴通风是一个自然的结果，在构造阶段的海底扩张，而轴上通风发生在岩浆为主的阶段。超镁铁质的Logatchev气田位于构造活动脊段的轴外，而玄武岩的5°S系统位于最近有岩浆活动的脊段的轴上。这些对比鲜明的热液喷口使它们成为实现我们目标的理想天然实验室。在DFG的优先计划1144“从地幔到海洋”期间获得的广泛背景数据和知识的基础上，我们现在准备使用最先进的数值模型来测试我们的主要假设。作为对热液喷发的大规模构造控制研究的补充，我们还将探索流体动力学对流体通道和化学的控制。通过这种综合方法，拟议的工作将使我们能够更密切地联系表面观测与远程物理化学过程在深度。

The proposed work aims at understanding the relationships between tectono-magmatic processes at slow spreading ridges and the origin and nature of hydrothermal venting. In particular, we will test if off-axis venting is a natural consequence of seafloor spreading in a tectonic phase, while on-axis venting occurs during magmatic dominated phases. The ultramafic hosted Logatchev field is located off-axis on a tectonically active ridge segment, while the basaltic hosted 5°S system is situated on the axis of a ridge segment with recent magmatic activity. These contrasting styles of hydrothermal venting make them ideal natural laboratories for our objectives. Building on the extensive background data and knowledge acquired during DFG‟s Priority Program 1144 “From Mantle to Ocean”, we are now poised to test our main hypothesis using state-of-the-art numerical models. As a complement to studies of large-scale tectonic controls on hydrothermal venting, we will also explore the fluid-dynamic controls on fluid pathways and chemistry. By this integrated approach, the proposed work will allow us to more closely link surface observations with remote physicochemical processes at depth.