Yang Jidong, Zhu Hejun, Zhao Zeyu, Huang Jianping, Lumley David, Stern Robert J, Dunn Robert A, Arnulf Adrien F, Ma Jianwei
National Key Laboratory of Deep Oil and Gas, School of Geosciences, China University of Petroleum (East China), Qingdao, Shandong, China.
Department of Sustainable Earth Systems Sciences, The University of Texas at Dallas, Richardson, TX, USA.
Nat Commun. 2024 Jun 4;15(1):4767. doi: 10.1038/s41467-024-49188-y.
The architecture of magma plumbing systems plays a fundamental role in volcano eruption and evolution. However, the precise configuration of crustal magma reservoirs and conduits responsible for supplying eruptions are difficult to explore across most active volcanic systems. Consequently, our understanding of their correlation with eruption dynamics is limited. Axial Seamount is an active submarine volcano located along the Juan de Fuca Ridge, with known eruptions in 1998, 2011, and 2015. Here we present high-resolution images of P-wave velocity, attenuation, and estimates of temperature and partial melt beneath the summit of Axial Seamount, derived from multi-parameter full waveform inversion of a 2D multi-channel seismic line. Multiple magma reservoirs, including a newly discovered western magma reservoir, are identified in the upper crust, with the maximum melt fraction of ~15-32% in the upper main magma reservoir (MMR) and lower fractions of 10% to 26% in other satellite reservoirs. In addition, a feeding conduit below the MMR with a melt fraction of ~4-11% and a low-velocity throat beneath the eastern caldera wall connecting the MMR roof with eruptive fissures are imaged. These findings delineate an asymmetric shallow plumbing system beneath Axial Seamount, providing insights into the magma pathways that fed recent eruptions.
岩浆管道系统的结构在火山喷发和演化过程中起着至关重要的作用。然而，在大多数活跃火山系统中，负责供应火山喷发的地壳岩浆储层和管道的精确形态很难探测清楚。因此，我们对它们与喷发动力学之间相关性的理解是有限的。轴海山是一座位于胡安德富卡洋脊的活海山，在1998年、2011年和2015年都有过已知的喷发活动。在此，我们展示了轴海山山顶下方的P波速度、衰减以及温度和部分熔融估计的高分辨率图像，这些图像是通过对一条二维多道地震测线进行多参数全波形反演得到的。在上地壳中识别出了多个岩浆储层，包括一个新发现的西部岩浆储层，在上部主岩浆储层（MMR）中最大熔体分数约为15% - 32%，在其他卫星储层中熔体分数较低，为10%至26%。此外，还成像了MMR下方熔体分数约为4% - 11%的输送管道以及连接MMR顶部与喷发裂缝的东火山口壁下方的低速通道。这些发现描绘了轴海山下方不对称的浅层管道系统，为近期喷发的岩浆通道提供了见解。
