Collaborative Research: Developing New Instrumentation to Accurately Measure the Heat and Mass Flux of Hydrothermal Fluids

PI申请资金用于开发一对专门设计的相机系统，用于使用OPV （VentCam）和DFV（漫射流出测量系统（DEMS））来测量这些环境中集中和漫射热液流的速度。VentCam系统将使用OPV对黑烟液进行时间序列速度测量，使用具有自动平移功能的高速高分辨率摄像机，在硫化物烟囱生长过程中保持视野内的流量。dem将使用一个固定距离的摄像机来测量扩散流体速度，该摄像机是专门为DFV计算而设计的。通过放置在高温排气孔中的热电偶以及与dem耦合的低温记录仪同时进行温度测量，将有助于限制扩散和集中热流的分配以及归因于轴向排气的地壳冷却量。测量热液流出地壳的速率，以及这些速率如何随时间变化，对于理解这些系统及其组成部分之间的复杂联系至关重要。这种测量可以提供有关海底渗透率结构、热液环流模式的几何形状、与上覆海洋交换的热量和化学物质的通量以及海底生态系统潜在生产力的信息。更广泛的影响：利用这些工具获得的知识将提高我们对热液流体通量及其对各种化学、生物和物理过程的贡献的理解。该项目将支持两名早期职业科学家，他们负责开发这些成像系统使用的光学方法。博士后的指导计划描述得很好，很可能导致研究人员在项目生命周期内的成功发展。在开发和测试后，如果与区域海底电缆观测站（如Juan de Fuca Ridge上正在开发的区域串行节点观测站）连接，这些仪器有可能获得更长期的时间序列。

The PI's request funding to develop a pair of camera systems that are specifically designed to use OPV (VentCam) and DFV (Diffuse Effluent Measurement System (DEMS)) to measure the velocities of focused and diffuse hydrothermal flows in these environments. The VentCam system will use OPV to perform time-series velocity measurements on black smoker fluids using a high-speed, high resolution camera with automatic panning that maintains the flow in the field-of-view during sulfide chimney growth. The DEMS will measure diffuse fluid velocities using a camera attached at a fixed distance from a background specially designed for DFV calculations. Simultaneous temperature measurements by thermocouples placed in high-temperature vent orifices as well as low-temperature loggers coupled to the DEMS will help constrain the partitioning of diffuse and focused heat fluxes and the amount of crustal cooling attributable to axial venting. Measuring the rates at which hydrothermal fluids exit the crust, and how those rates change over time, is critical for understanding these systems and the complex linkages between their component parts. Such measurements can provide information about the structure of permeability in the subseafloor, the geometry of hydrothermal circulation patterns, fluxes of heat and chemicals exchanged with the overlying ocean, and the potential productivity of subseafloor ecosystems.Broader Impacts: Knowledge gained using these tools will improve our understanding of hydrothermal fluid fluxes and their contribution to a variety of chemical, biological and physical processes. The project will support two early career scientists who were responsible for developing the optical methods to be used by these imaging systems. The Mentoring plan for the post-doc is well described and likely to result in successful development of the researcher during the projects lifetime. When developed and tested, the instruments have potential for longer-term time series if connected to regional seafloor cabled observatories like the Regional Serial Nodes observatory under development on the Juan de Fuca Ridge.