气候变化领域集成服务门户(CCPortal): Optimal depth of subvolcanic magma chamber growth controlled by volatiles and crust rheology

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DOI	10.1038/s41561-019-0415-6
	Optimal depth of subvolcanic magma chamber growth controlled by volatiles and crust rheology
	Huber C.; Townsend M.; Degruyter W.; Bachmann O.
发表日期	2019
ISSN	17520894
卷号	12 期号:9
英文摘要	Storage pressures of magma chambers influence the style, frequency and magnitude of volcanic eruptions. Neutral buoyancy or rheological transitions are commonly assumed to control where magmas accumulate and form such chambers. However, the density of volatile-rich silicic magmas is typically lower than that of the surrounding crust, and the rheology of the crust alone does not define the depth of the brittle–ductile transition around a magma chamber. Yet, typical storage pressures inferred from geophysical inversions or petrological methods seem to cluster around 2 ± 0.5 kbar in all tectonic settings and crustal compositions. Here, we use thermomechanical modelling to show that storage pressure is controlled by volatile exsolution and crustal rheology. At pressures ≲ 1.5 kbar, and for geologically realistic water contents, chamber volumes and recharge rates, the presence of an exsolved magmatic volatile phase hinders chamber growth because eruptive volumes are typically larger than recharges feeding the system during periods of dormancy. At pressures ≳ 2.5 kbar, the viscosity of the crust in long-lived magmatic provinces is sufficiently low to inhibit most eruptions. Sustainable eruptible magma reservoirs are able to develop only within a relatively narrow range of pressures around 2 ± 0.5 kbar, where the amount of exsolved volatiles fosters growth while the high viscosity of the crust promotes the necessary overpressurization for eruption. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	crust; crustal structure; exsolution; geophysical method; magma; magma chamber; rheology; tectonic setting; volatile substance; volcanic eruption
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124610
作者单位	Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States; Department of Earth Sciences, University of Oregon, Eugene, OR, United States; School of Earth and Ocean Sciences, Cardiff University, Cardiff, United Kingdom; Department of Earth Sciences, ETH Zurich, Zurich, Switzerland
推荐引用方式 GB/T 7714	Huber C.,Townsend M.,Degruyter W.,et al. Optimal depth of subvolcanic magma chamber growth controlled by volatiles and crust rheology[J],2019,12(9).
APA	Huber C.,Townsend M.,Degruyter W.,&Bachmann O..(2019).Optimal depth of subvolcanic magma chamber growth controlled by volatiles and crust rheology.Nature Geoscience,12(9).
MLA	Huber C.,et al."Optimal depth of subvolcanic magma chamber growth controlled by volatiles and crust rheology".Nature Geoscience 12.9(2019).