During volcanic eruptions, the interaction of magma and groundwater can produce thermohydraulic explosions capable of significantly increasing the eruption energy. The most well-known mechanism by which explosive magma–water interactions occur, molten fuel–coolant interaction (MFCI), is a complex series of macro- and microscale processes which have been simulated using laboratory-scale experiments. As a natural analog for MFCI experiments, we utilize rootless cone beds formed by lava–water explosions to estimate explosion energy. The specific mechanical energy of the lava–water explosions studied here occurs over a broader range (4 to 178 kJ/kg) than MFCI experiments and includes estimates for the highest-energy lava–water explosions studied to date. Explosion energy is partitioned similarly over the two systems, with kinetic transport and fragmentation energy making up 25–40% and 42–80% of the mechanical energy, respectively, which overlap the ranges estimated for MFCI experiments. Our study of lava–water explosions therefore provides a field-scale analog of MFCI laboratory experiments for understanding the energetics, and therefore hazards, of MFCI in natural systems.

中文翻译：

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利用无根锥状沉积物的特征来估计爆炸性熔岩-水相互作用的能量学

在火山喷发期间，岩浆和地下水的相互作用可以产生能够显着增加喷发能量的热力水力爆炸。发生爆炸性岩浆-水相互作用的最著名机制，即熔融燃料-冷却剂相互作用 (MFCI)，是一系列复杂的宏观和微观过程，已使用实验室规模的实验进行模拟。作为 MFCI 实验的自然模拟，我们利用由熔岩-水爆炸形成的无根锥床来估计爆炸能量。此处研究的熔岩-水爆炸的比机械能发生在比 MFCI 实验更广的范围内（4 到 178 kJ/kg），并且包括迄今为止研究的最高能量熔岩-水爆炸的估计值。爆炸能量在两个系统中的分配相似，动能传输和破碎能分别占机械能的 25-40% 和 42-80%，与 MFCI 实验估计的范围重叠。因此，我们对熔岩-水爆炸的研究提供了 MFCI 实验室实验的现场规模模拟，用于了解自然系统中 MFCI 的能量学和危害。