Temporal evolution of hydrothermal systems at the Mid-Atlantic Ridge (14°45 - 15°05N)

洋中脊热液活动是地幔与海洋之间热质交换的重要因素。关于热液系统的寿命、其随时间的变化或热液溶液的化学性质随时间的变化的资料很少。将在利用天然放射性核素确定热液矿床年龄的基础上，调查洛加切夫地区热液活动的持续时间和周期性，并首次调查大西洋中脊北纬15度热液地区的热液活动，这些热液活动是由超镁铁岩的蛇纹石化造成的。根据热液矿床的地球化学和年龄，将获得关于地质历史期间热液流体变化的信息。热液流体在地壳中的停留时间对其化学成分的重要性将针对Logatchev油田的不同流体喷发进行研究。这些研究是以将在FS Meteor M60/3号沿着沿北纬14°45至15°05之间的大西洋中脊进行的流体和热液沉淀物取样为基础的。

Hydrothermal activity at mid-oceanic ridges is an important factor for the heat and mass transfer between the mantle and the ocean. Little information is available on the life-span of hydrothermal systems, their temporal variability or changes of the chemistry of hydrothermal solutions with time. Based on age determinations of hydrothermal deposits by means of natural radionuclides, the duration and periodicity of hydrothermal activity shall be investigated in the Logatchev field and, for the first time, in hydrothermal fields at 15°N at the Mid-Atlantic Ridge, which are due to serpentinization of ultramafic rocks. Based on the geochemistry and the ages of the hydrothermal deposits information on the variability of the hydrothermal fluids during the geological past will be obtained. The importance of the residence time of hydrothermal fluids in the crust for their chemical composition will be investigated for the different fluids venting at the Logatchev field. These studies are based on sampling of fluids and hydrothermal precipitates which will be conducted during the FS Meteor cruise M60/3 along the Mid-Atlantic Ridge between 14°45 N and 15°05 N.