Collaborative Research: Development and fabrication of a high-temperature borehole fluid sampler to characterize seawater-basalt reactions and the thermal limits of life on Earth

合作研究：开发和制造高温钻孔流体采样器，以表征海水-玄武岩反应和地球上生命的热极限

• 批准号: 1829670
• 负责人: Christopher Kitts
• 金额: $ 27.24万
• 依托单位: Santa Clara University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-15 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829670&HistoricalAwards=false
• 关键词: Collaborative; Research; Development; fabrication; temperature

Five decades of scientific ocean drilling have created more than 113-cased boreholes in the ocean. Such legacy boreholes have been drilled into a range of seafloor geologic settings and many of these boreholes are deep enough that natural geothermal gradients have warmed the boreholes to temperatures in the range (60-200 degrees C). Within this temperature range reactions pathways between seawater and basalt change, affecting how the basaltic crust ages through the dissolution of primary minerals and the precipitation of different minerals as veins, for example. This combination of dissolution and precipitation changes the characteristics of the ocean crust that ultimately affects how the crust is subducted and the potential for large destructive earthquakes. This temperature range also spans the thermal limits of microbial life, based on experiments (122 degrees C), theoretical calculations (150 degrees C), and anecdotal evidence (180 degrees C). However the scientific drilling community currently lacks the ability to collect such warm pristine borehole fluids because electronics fail at such temperatures. This project will solve this sampling problem by first testing shape memory alloys, which are metal alloys that can change their shape and length at a specific temperature that is a function of the alloy composition and fabrication process. Then a water sampling system will be developed that utilizes the properties of shape memory alloys to trigger the collection of boreholes fluids. The first deployment of the newly fabricated system will occur in July 2019 when the scientific drilling program re-enters a legacy borehole that is ~200 degrees C at the base of the hole. The broader impacts of this project will provide the scientific community with a new sampling system for collecting borehole fluids at elevated temperatures. Such a sampling system is not limited to oceanic boreholes, but could be used within the thousands of existing continental boreholes. This new high temperature fluid sampling system will allow the community to explore new directions in understanding hydrothermal processes. Hydrothermal processes and the thermal limits of life are exciting topics that engage the public. More specifically the proposed work will include the development of a hands-on module for a week-long summer day camp (ssrovcamp.org) for rising 3-5th and 6-9th grade students and students involved in the undergraduate marine education program at Santa Clara University. Combined, over 300 students were engaged in one of these two programs in 2018.The crux of this project is to design and fabricate a fluid sampling system for high temperature 60-200 degrees C borehole applications in oceanic and continental settings. The project will build on a Provisional Patent to design and fabricate standard titanium syringe-like fluid capture systems that are triggered by a novel mechanism. This mechanism will use shape memory alloys, given that such alloys change shape at a particular temperature. The sampling system will be modular in design to allow a suite of samples to be collected on a single lowering, each sampler collecting fluid at a specific temperature depending on the particular shape memory alloy that is used in that sampler. This system will be designed to be deployable from oceanic drilling vessels, continental drilling rigs, and submersibles/remotely operated vehicles (ROVs).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

五十年的科学海洋钻探在海洋中创造了113多个井眼。这种传统的钻孔已被钻入一系列海底地质环境中，其中许多钻孔足够深，以至于天然地热梯度使钻孔温暖到范围内的温度（60-200摄氏度）。例如，在此温度范围内，海水和玄武岩变化之间的反应途径，影响玄武岩外壳如何通过原代矿物质的溶解和不同矿物作为静脉的沉淀而变化。这种溶解和降水的结合改变了海壳的特征，最终影响地壳的俯冲方式和大型破坏性地震的潜力。根据实验（122度C），理论计算（150度C）和轶事证据（180度C），该温度范围还跨越微生物寿命的热限。然而，科学钻探社区目前缺乏收集此类温暖原始钻孔流体的能力，因为电子产品在这种温度下失败。该项目将通过首先测试形状内存合金来解决此采样问题，这些金属合金可以在特定温度下改变其形状和长度，这是合金组成和制造过程的函数。然后将开发一个水采样系统，该系统利用形状存储合金的特性触发钻孔流体的收集。新制造系统的首次部署将于2019年7月发生，当时科学钻探计划重新进入了孔的底部约200度C的传统钻孔。该项目的更广泛影响将为科学界提供一种新的抽样系统，用于在升高温度下收集钻孔液。这样的采样系统不仅限于海洋钻孔，但可以在数千个现有的大陆钻孔中使用。这种新的高温流体采样系统将使社区能够探索了解水热过程的新方向。水热过程和生活的热限制是吸引公众的令人兴奋的主题。更具体地说，拟议的工作将包括开发为期一周的夏季营地（SSROVCAMP.org）的动手模块，以增加3-5岁和6-9岁的学生以及参与圣克拉拉大学本科生教育计划的学生。在2018年，共有300多名学生参与了这两个计划之一。该项目的症结在于在海洋和大陆环境中设计和制造高温60-200摄氏度的液体采样系统。该项目将建立在设计和制造标准的钛样的注射器样流体捕获系统的临时专利基础上，该专利是由新型机制触发的。鉴于这种合金在特定温度下改变形状，该机制将使用形状的内存合金。采样系统的设计将是模块化的，以允许在单个降低上收集一套样品，每个采样器在特定温度下收集流体，具体取决于该采样器中使用的特定形状存储合金。该系统将设计为可以从海洋钻探船，大陆钻机和潜水员/远程操作的车辆（ROVS）中部署。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的审查标准通过评估来通过评估来支持的。

项目成果

A new high-temperature borehole fluid sampler: the Multi-Temperature Fluid Sampler

新型高温钻孔流体采样器：多温流体采样器

• DOI: 10.5194/sd-28-43-2020
• 发表时间: 2020
• 期刊: Scientific Drilling
• 影响因子: 1.2
• 作者: Wheat, C. Geoffrey;Kitts, Christopher;Webb, Camden;Stolzman, Rachel;McGuire, Ann;Fournier, Trevor;Pettigrew, Thomas;Jannasch, Hans
• 通讯作者: Jannasch, Hans