X-ray tomography and acoustic emissions of in situ, time-resolved magma fracturing: insights into the causes of explosive volcanic eruptions

We propose to use the KORE rig installed at the beamline ID19 at ESRF, coupled with X-ray tomography and acoustic emissions to simulate conditions relevant to magma fracturing prior to and at the onset of explosive volcanic eruptions. We specifically plan to record the in situ, time-resolved evolution of the synthetic magma microstructures and the sound waves produced by sample fracturing at conditions of temperature and stress of magma fragmentation leading to explosive eruptions relevant to shallow (< 4 km depth) magma reservoirs feeding active volcanoes. These results offer the opportunity to better illuminate the causes of explosive eruptions and, with appropriate upscaling, how to apply seismic imaging for detecting the proximity of gas-rich magma to the surface.

本研究拟采用安装于欧洲同步辐射装置（ESRF）ID19束线的KORE实验装置，结合X射线断层扫描（X-ray tomography）与声发射（acoustic emissions）技术，模拟爆炸性火山喷发前及喷发初期与岩浆破裂相关的物理条件。本研究将针对性记录合成岩浆微观结构的原位、时间分辨演化过程，以及在与供给活火山的浅部（深度小于4千米）岩浆房相关的、可引发爆炸性喷发的岩浆碎裂温度与应力条件下，样品破裂产生的声波信号。上述研究结果有助于更清晰地阐明爆炸性火山喷发的成因，且经合理尺度放大后，可为利用地震成像（seismic imaging）探测富气岩浆距地表的远近提供可行路径。