Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA. Seismological Laboratory, California Institute of Technology, Pasadena, CA 91125, USA.
Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA.
Science. 2015 May 15;348(6236):773-6. doi: 10.1126/science.aaa5648. Epub 2015 Apr 23.
The Yellowstone supervolcano is one of the largest active continental silicic volcanic fields in the world. An understanding of its properties is key to enhancing our knowledge of volcanic mechanisms and corresponding risk. Using a joint local and teleseismic earthquake P-wave seismic inversion, we revealed a basaltic lower-crustal magma body that provides a magmatic link between the Yellowstone mantle plume and the previously imaged upper-crustal magma reservoir. This lower-crustal magma body has a volume of 46,000 cubic kilometers, ~4.5 times that of the upper-crustal magma reservoir, and contains a melt fraction of ~2%. These estimates are critical to understanding the evolution of bimodal basaltic-rhyolitic volcanism, explaining the magnitude of CO2 discharge, and constraining dynamic models of the magmatic system for volcanic hazard assessment.
黄石超级火山是世界上最大的活陆相硅酸火山活动区之一。了解其性质是增强我们对火山机制和相应风险认识的关键。我们使用联合局部和远震地震 P 波地震反演，揭示了一个玄武质下地壳岩浆体，它为黄石地幔柱和以前成像的上地壳岩浆库之间提供了岩浆联系。这个下地壳岩浆体的体积为 46000 立方公里，约为上地壳岩浆库的 4.5 倍，含有约 2%的熔体分数。这些估计对于理解双峰玄武岩-流纹岩火山作用的演化、解释 CO2 排放量的大小以及约束岩浆系统的动力学模型以进行火山灾害评估至关重要。
