研究人员使用了沿着穿过火山口100千米长的光缆，并利用其记录的分布式声学传感数据来成像其地下结构。图像突出了浅层热液系统和位于约12千米深处的大型岩浆库之间的明确分离。地质证据与研究结果相结合表明，流体是如何通过第二次沸腾溶出的，并提供了观测到的隆起和地震活动的来源。
据介绍，火山口的地球物理特征是评估其未来灾难性火山爆发可能性的基础。加州长谷火山口动荡背后的机制仍然备受争议，有学者认为近期的隆起和地震活动要么是由岩浆房释放的水基流体驱动的，要么是由岩浆侵入上上地壳驱动的。
附：英文原文
Title: An upper-crust lid over the Long Valley magma chamber
Author: Ettore Biondi, Weiqiang Zhu, Jiaxuan Li, Ethan F. Williams, Zhongwen Zhan
Issue&Volume: 2023-10-20
Abstract: Geophysical characterization of calderas is fundamental in assessing their potential for future catastrophic volcanic eruptions. The mechanism behind the unrest of Long Valley Caldera in California remains highly debated, with recent periods of uplift and seismicity driven either by the release of aqueous fluids from the magma chamber or by the intrusion of magma into the upper crust. We use distributed acoustic sensing data recorded along a 100-kilometer fiber-optic cable traversing the caldera to image its subsurface structure. Our images highlight a definite separation between the shallow hydrothermal system and the large magma chamber located at ~12-kilometer depth. The combination of the geological evidence with our results shows how fluids exsolved through second boiling provide the source of the observed uplift and seismicity.
DOI: adi9878
Source: https://www.science.org/doi/10.1126/sciadv.adi9878