In-Situ Chemical Sensors for Monitoring the Chemistry of Hydrothermal Vent Fluids at Mid-Ocean Ridges: Instrument Development and Field Applications

摘要：丁（0525907）智力优势：测量和监测极端环境下水体化学变化的能力是一项重大的技术和科学挑战。本研究将继续开发、校准、测试和部署现场电化学传感器，用于pH、温度和重要的含氢和含硫氧化还原化合物，目的是生产一种仪器包，可用于长期监测大洋中脊的热液喷口化学。该仪器的原型测试已经成功，并实时测量了从高温和低温扩散流喷口发出的水中的pH和H2和H2S浓度。这项工作将扩展传感器阵列的监测能力，并增加其在海底长期部署的物理稳健性。现场测试地点将是东太平洋隆起的高温和低温漫流喷口，以及失落之城的低温喷口或大西洋中脊的彩虹喷口。将对固态pH传感器的材料特性进行长期实验室测试，并将结果广泛传播，以建立用户群。具体项目目标包括当前高温传感器包的原位计算机控制校准和固态pH传感器的开发，该传感器更适合在高pH和生物活性热液喷口地区长期使用。该计划的第一年将致力于现有化学传感器系统的技术升级。传感器包的现场部署和测试将于第二年和第三年在EPR 9N和MAR热液站点使用潜水器和/或rov进行。更广泛的影响：这项工作资助了明尼苏达大学的研究人员和学生。更广泛的影响包括新的传感器/工具的开发，以及在温度、压力、腐蚀性化学和/或生物污染等方面过于恶劣的环境中应用这些工具，无法进行现场采样和测量。因此，这项工作增强了海洋科学界可用的研究基础设施，特别是在对海洋中脊的能量和质量传递相关的内在动力学过程进行关键的时间序列测量方面。

Abstract: Ding (0525907)Intellectual Merit: The ability to measure and monitor changes in the chemistry of waters from extreme environments is a major technological and scientific challenge. This research continues an ongoing effort to develop, calibrate, test, and deploy in situ electrochemical sensors for pH, temperature, and important Hydrogen and sulfur-bearing redox compounds, with the goal of producing an instrument package that can be used for long term monitoring of hydrothermal vent chemistry at mid-ocean ridges. Prototype testing of the instrument has been successful and measured, in real time, the in situ pH and H2 and H2S concentrations of waters emanating from high and low temperature, diffuse-flow vents. This work will extend the monitoring capabilities of the sensor array and increase its physical robustness for long-term deployment on the seafloor. Field test sites will be high temperature and low temperature diffuse flow vents on the East Pacific Rise and low temperature vents at Lost City or the Rainbow site on the Mid Atlantic Ridge. Long-term lab testing of the material properties of the sensors will be carried out for the solid-state pH sensor and results will be disseminated widely to build a user base. Specific project goals include in-situ computer controlled calibration of the present high temperature sensor package and the development of a solid-state pH sensor, which is better suited for long-term use in high pH and biologically active hydrothermal vent areas. The first year of the program will be devoted to technical upgrades of the present chemical sensor system. Field deployments and testing of the sensor packages will take place in years two and three at the EPR 9N and MAR hydrothermal sites using submersibles and/or ROVs.Broader Impacts: This work funds researchers and students at the University of Minnesota. Broader impacts consist of new sensor/tool development and application of the tools in environments previously too hostile, in terms of temperature, pressure, corrosive chemistry and/or biofouling, to be sampled and measured in-situ. As such, this work enhances research infrastructure available to the ocean sciences community, especially with regard to making crucial time series measurements of inherently dynamical processes linked to energy and mass transfer at mid-ocean ridges.