Geochemical Constraints on Light Emission in Seafloor Hydrothermal Systems: An Experimental Study Using In-Situ Spectral and Chemical Sensor Techniques

最近，潜水器ALVIN上部署的高灵敏度CCD相机系统进行了研究，发现海底热液喷口发出了光。总的来说，这些研究揭示了喷口流体的光子通量超过了简单黑体辐射预测的光子通量，这表明存在一些原位发光过程。特别是，化学发光（伴随化学反应的光发射）、声发光（由蒸汽泡内爆或空化发出的光）或晶体发光（伴随矿物沉淀的光发射）被认为是最可能解释这一现象的过程。本研究旨在明确评估在适用于海洋热液系统的温度和压力下由化学反应、蒸汽产生、效应和结晶过程产生的光的强度和光谱特征。根据该合同，pi将使用一系列计算机控制的ti流反应器，修改后包含光学窗口、光纤电缆、光谱仪和CCD探测器，从而可以测量和监测光的强度和光谱变化。实验将专门评估化学发光、声发光和晶体发光在适当的温度、压力、成分效应和流体流速范围内对光产生的作用。这些实验将包括一些原位化学传感器，以便在实验期间更好地约束含水物种的分布，同时将这些数据与光谱观测联系起来。

Recent studies with highly sensitive CCD camera systems deployed from the submersible ALVIN have revealed light being emitted from hydrothermal fluids venting at the ocean floor. In general, these studies reveal photon fluxes from the vent fluids in excess of those predicted from simple blackbody radiation, suggesting a number of in-situ light-generating processes. In particular, chemiluminescence (emission of light that accompanies chemical reactions), sonoluminescence (light emitted by vapor bubble implosion or cavitation), or crystalloluminescence (emission of light accompanying onset of mineral precipitation) are thought to be the mose likely processes to account for this. This investigation is designed to assess unambiguously the intensity and spectral characteristics of light generated by chemical reactions, vapor generation, effects and crystallization processes at temperatures and pressures applicable to marine hydrothermal systems. Under this award, the PIs will use a series of computer controlled Ti-flow reactors, modified to contain optical windows, fiber optic cables, spectrometer, and CCD detector that will allow the intensity and spectral variability of light to be measured and monitored. The experiments will be designed to specifically assess the role of chemiluminescence, sonoluminescence and crystalloluminescnce on light generation for an appropriate range of temperatures, pressures, compositional effects, and fluid flow rates. The experiments will include a number of in-situ chemical sensors developed at to better constrain the distribution of aqueous species during the experiments, while simultaneously linking these data to spectral observations.