Abstract Recent advances in the development of in-situ chemical and temperature sensors have shown great promise as a means to investigate time series changes in marine and terrestrial hydrothermal systems. Here we apply this technology to assess chemical and physical controls on sublacustrine vent fluids in Yellowstone Lake, WY. Autonomous sensor systems were deployed in August 2017 using ROV assets to position instruments at two sites in the Deep Hole region of the Lake, off-shore from Stevenson Island. Earlier studies have documented that fissure related depressions (~120 m water depth) in this region host numerous vents issuing high enthalpy, CO2 saturated and H2S bearing vapor, at temperatures in excess of 150 °C. The YSZ (ceramic)-based in-situ chemical sensors deployed here were designed to measure pH and redox at 60 s intervals for up to one year. Two titanium-sheathed thermocouples, one coupled directly to the electrochemical sensor and another, independently powered and positioned slightly deeper in vents at deployment sites, provided insight on maximum temperature in the near surface region. In addition to in-situ chemical and temperature data, vent fluid samples were acquired at the outset and during recovery with a novel isobaric system that maintains lake bottom pressure, precluding fluid-sample de-gassing. At the same time, push cores of vents and in the near vent region were also acquired. The mineralized cores provide evidence of long term mass transfer processes, while also facilitating insertion and stabilization of the sensor units on the lake floor. Recovery of the sensors documented similar chemical controls at both sites, suggesting compositionally invariant vapor influx, characterized by moderately low pH (~4–5) and reducing conditions, buffered by CO2 and H2S, respectively. Accordingly, the diatomaceous sediment was extensively altered to kaolinite and pyrite. Temperature variability at the two sites was especially significant. One site (Site B), situated on the slope of what might be a hydrothermal domal structure, demonstrated noteworthy cooling and heating episodes that may be associated with hydrothermally or seismically triggered sediment slumping events. Upon instrument recovery in 2018, the vent site was largely sediment covered and the sensor insert showed evidence of dis-location and melting by conductive heating under the hot sediment overburden. The initially active and high temperature vent fluid (~148 °C) had largely ceased and replaced by diffuse flow venting at the margin of the previous up-flow zone. The time series in-situ chemical and physical data obtained in the course of the study document the existence of a dynamic hydrothermal system in time and space, while underscoring the challenges of research of this type in such environments.

中文翻译：

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怀俄明州黄石湖湖底喷口的热量和质量传输：记录动态热液系统的原位化学和温度数据

摘要 原位化学和温度传感器发展的最新进展显示出作为研究海洋和陆地热液系统时间序列变化的一种手段的巨大希望。在这里，我们应用这项技术来评估对怀俄明州黄石湖湖底喷口流体的化学和物理控制。自主传感器系统于 2017 年 8 月部署，使用 ROV 资产在史蒂文森岛离岸的湖深洞地区的两个地点定位仪器。较早的研究表明，该地区与裂隙相关的洼地（~120 m 水深）有许多喷口，在超过 150 °C 的温度下释放出高焓、CO2 饱和和含 H2S 的蒸汽。此处部署的基于 YSZ（陶瓷）的原位化学传感器旨在以 60 秒的间隔测量 pH 值和氧化还原，最长可达一年。两个钛护套热电偶，一个直接耦合到电化学传感器，另一个独立供电并位于部署地点的通风口中稍深的位置，提供了对近地表区域最高温度的洞察。除了原位化学和温度数据外，在开始和恢复过程中，使用一种保持湖底压力的新型等压系统采集排放流体样品，防止流体样品脱气。同时，还获得了喷口和近喷口区域的推芯。矿化核心提供了长期传质过程的证据，同时也有助于传感器单元在湖底的插入和稳定。传感器的回收记录了两个地点的类似化学控制，表明成分不变的蒸汽流入，其特征是适度低的 pH 值（~4-5）和还原条件，分别由 CO2 和 H2S 缓冲。因此，硅藻沉积物被广泛地改变为高岭石和黄铁矿。两个地点的温度变化尤其显着。一个站点（站点 B）位于可能是热液穹顶结构的斜坡上，显示出值得注意的冷却和加热事件，这些事件可能与热液或地震引发的沉积物坍塌事件有关。2018年仪器恢复后，通风口大部分被沉积物覆盖，传感器插件显示出在热沉积物覆盖层下通过传导加热发生错位和熔化的证据。最初活跃的高温排放流体 (~148 °C) 已在很大程度上停止，取而代之的是在先前上流区边缘的扩散流排放。在研究过程中获得的时间序列原位化学和物理数据记录了时空动态热液系统的存在，同时强调了在此类环境中进行此类研究的挑战。