气候变化领域集成服务门户(CCPortal): Storage and Evolution of Laguna del Maule Rhyolites: Insight From Volatile and Trace Element Contents in Melt Inclusions

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DOI	10.1029/2020JB019475
	Storage and Evolution of Laguna del Maule Rhyolites: Insight From Volatile and Trace Element Contents in Melt Inclusions
	Klug J.D.; Singer B.S.; Kita N.T.; Spicuzza M.J.
发表日期	2020
ISSN	21699313
卷号	125 期号:8
英文摘要	Interpreting unrest at silicic volcanoes requires knowledge of the magma storage conditions and dynamics that precede eruptions. The Laguna del Maule volcanic field, Chile, has erupted ~40 km3 of rhyolite over the last 20 ka. Astonishing rates of sustained surface inflation at >25 cm/year for >12 years reveal a large, restless system. Integration of geochronologic, petrologic, geomorphic, and geophysical observations provides an unusually rich context to interpret ongoing and prehistoric processes. We present new volatile (H2O, CO2, S, F, and Cl), trace element, and major element concentrations from 109 melt inclusions hosted in quartz, plagioclase, and olivine from seven eruptions. Silicic melts contain up to 8.0 wt. % H2O and 570 ppm CO2. In rhyolites melt inclusions track decompression-driven fractional crystallization as magma ascended from ~14 to 4 km. This mirrors teleseismic tomography and magnetotelluric findings that reveal a domain containing partial melt spanning from 14 to 4 km. Ce and Cl contents of rhyolites support the generation of compositionally distinct domains of eruptible rhyolite within the larger reservoir. Heat, volatiles, and melt derived from episodic mafic recharge likely incubate and grow the shallow reservoir. Olivine-hosted melt inclusions in mafic tephra contain up to 2.5 wt. % H2O and 1,140 ppm CO2 and proxy for the volatile load delivered via recharge into the base of the silicic mush at ~14 to 8 km. We propose that mafic recharge flushes deeper reaches of the magma reservoir with CO2 that propels H2O exsolution, upward accumulation of fluid, pressurization, and triggering of rhyolitic eruptions. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Laguna del Maule; magma storage; melt inclusion; rhyolite; southern volcanic zone; volatiles
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187688
作者单位	Department of Geoscience, University of Wisconsin-Madison, Madison, WI, United States
推荐引用方式 GB/T 7714	Klug J.D.,Singer B.S.,Kita N.T.,et al. Storage and Evolution of Laguna del Maule Rhyolites: Insight From Volatile and Trace Element Contents in Melt Inclusions[J],2020,125(8).
APA	Klug J.D.,Singer B.S.,Kita N.T.,&Spicuzza M.J..(2020).Storage and Evolution of Laguna del Maule Rhyolites: Insight From Volatile and Trace Element Contents in Melt Inclusions.Journal of Geophysical Research: Solid Earth,125(8).
MLA	Klug J.D.,et al."Storage and Evolution of Laguna del Maule Rhyolites: Insight From Volatile and Trace Element Contents in Melt Inclusions".Journal of Geophysical Research: Solid Earth 125.8(2020).