SGER: Design, Construction and Testing of Prototype Instrument for Contamination-Free Sampling of Crustal Fluids from Deep-Sea Boreholes

这是一项探索性研究（SGER）小额赠款，用于支持海洋地壳流体井下取样器（DS）的设计、建造和测试；DS的后续版本还将允许井下原位孵育。在井底直接收集流体应避免在流体上升到地面的过程中对流体成分施加的潜在变化。DS将用于研究基底地壳地球化学和物理条件下的微生物群落结构。该项目将与伍兹霍尔海洋研究所的克雷格·泰勒（Craig Taylor）的团队合作，展示从老化的、沉积物掩埋的海洋基底地壳中收集未受污染液体的可行性。开发一种可以从这种极端环境中收集无污染样品的新采样设备是一项冒险的努力。因此，团队将：1)进行初步的岸基钻孔模拟；2)使用溶解示踪剂、颗粒示踪剂和微生物示踪剂测试进样系统获得洁净样品的能力；3)将钻孔底部原始地壳流体的化学成分、微生物多样性和群落结构与整个钻孔和海水收集的地壳流体进行比较，以确定钻孔对上升流体的影响的性质和程度。这项提议的工作代表了探索海底生物圈的先驱尝试。利用来自这一广阔而未开发的新环境的真实样本来阐明微生物的代谢过程和生态学的潜力是很高的，因为发现具有新代谢途径的新生物的潜力也是很高的。

This is a Small Grant for Exploratory Research (SGER) award to support design, building and testing of a Downhole Sampler (DS) for ocean crustal fluids; subsequent versions of the DS will also permit downhole in situ incubations. Direct collection of fluids at the bottom of the borehole should avoid the potential changes imposed on the fluid composition during its ascent to the surface. The DS will be used to study the microbial community structure in the context of geochemical and physical conditions of the basement crust. The PI, in collaboration with Craig Taylor's group at the Woods Hole Oceanographic Institution, will demonstrate the feasibility of collecting uncontaminated fluids from aging, sediment-buried ocean basement crust. Development of a new sampling device that can collect contamination-free samples from this extreme environment is a risky endeavor. Accordingly, the team will: 1) Perform preliminary shore-based borehole simulations; 2) use dissolved, particle and microbial tracers to test the ability of the inlet system to obtain clean samples; and 3) compare the chemistry, microbial diversity, and community structure of pristine crustal fluids at the bottom of the borehole with those collected throughout the borehole and with seawater in order to establish the nature and magnitude of any influence of the borehole on the ascending fluids.The proposed work represents a pioneer attempt to explore the biosphere present in the sub-sea floor. The potential to elucidate the metabolic processes and ecology of microorganisms with authentic samples from this vast and unexplored new environment is high, as is the potential for discovery of novel organisms with new metabolic pathways.