Heat discharge at the dynamic magma-water-interface in subaqueous and subglacial volcanism: Experiments and thermodynamic modelling

在水下/冰下喷发期间，已观察到热脉冲。这些喷发提供了时间尺度和热效应的定量信息。为了直接测量从岩浆熔体到冷却剂的热通量，建立了一个短期量热计。在第一个系列中，使用了最近冰岛火山喷发的材料和纯净水，并且可以通过非爆炸过程产生颗粒，这实际上与天然透明质碎屑岩相同。通过熔体性质和实验几何的变化，也可以产生平坦的水和深海特征。实验产品的热-机械能收支的初步近似与2004年Grimsvötn火山喷发的数据吻合得很好。热力学模型的发展正在进行中。首先用不纯冷却剂进行的实验表明，冷却剂的热容量和粘度对热排放有重大影响。下一步计划进行详细的研究。地震信号记录显示出破碎和热通量的同步性，热微脉冲和地震微脉冲可用于实验监测。目的是利用高分辨率压力传感器直接监测声发射。如果可以指定“声指纹”，则可以在潜水器或探头上使用适当的传感器进行直接监测。

During subaqueous/subglacial eruptions, thermal pulses have been observed. These eruptions provide quantitative information on time scales and thermal efficacy. A short-term calorimeter was built for the direct measurement of the heat-flux from a magmatic melt to a coolant. In the first series material from recent eruptions in Iceland and purified water were used and particles could be pro-duced in a non-explosive process, that are practical identical to those from natural hyaloclastites. By variations of melt properties and experimental geometry flat water and deep sea signatures could be produced as well. First approximations of the thermo-mechanical energy budget of the experimental products are in good agreement with data of the 2004 Grimsvötn eruption. The development of a thermodynamic model is in progress. First experiments with impure coolants show, that heat capacity and viscosity of the coolant have a major impact on the heat discharge. Detailed studies are planned in the next step. The records of seismic signals show the synchronicity of fragmentation and heat-flux: thermal and seismic micro-pulses can be used for monitoring during the experiments. It is intended to use high resolution pressure sensors to monitor the acoustic emission directly. If “acoustical fingerprints” can be assigned, direct monitoring using appropriate sensors on submersibles or probes may be possible.