No single model for supersized eruptions and their magma bodies
No single model for supersized eruptions and their magma bodies
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DOI：
10.1038/s43017-021-00191-7
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发表时间：
2021-07
影响因子：
42.1
通讯作者：
C. Wilson;G. Cooper;K. Chamberlain;S. Barker;M. Myers;F. Illsley‐Kemp;J. Farrell
中科院分区：
文献类型：
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作者：
C. Wilson;G. Cooper;K. Chamberlain;S. Barker;M. Myers;F. Illsley‐Kemp;J. Farrell
超级火山爆发是地球上最大的火山爆发。它们产生灾难性的、广泛的火山灰降落毯和大量的熔结凝灰岩，伴随着火山口的坍塌。然而，母岩浆体的生成、储存和排空机制仍存在争议。在这篇综述中，我们综合了来自13个第四纪超喷发的野外、实验室和岩石学证据，以说明这些现象的多样性范围。超级爆发可以在几周到几个月内温和地开始，然后升级为高潮活动，或者立即进入剧烈活动。个别的超级爆发可以持续几天到几周，或者持续几十年。岩浆来源从单一岩浆体到同时或顺序开采的多个岩浆体。在所有13种情况下，富含晶体（>50-60%晶体）的岩浆系统的深根（>10公里）的寿命为数万至数十万年或更长。相比之下，喷发的岩浆在较浅的深度（4-10公里）在较短的时间尺度上聚集，有时在几个世纪内。过去事件的地质知识，结合现代地球物理技术，展示了大型的火山口火山（过去有过超级爆发）今天是如何运作的。未来的研究特别需要更好地限制现代火山动荡背后的过程以及可能预示即将发生的火山爆发的信号，无论规模大小。
Supereruptions are the largest explosive volcanic eruptions on Earth. They generate catastrophic, widespread ash-fall blankets and voluminous ignimbrites, with accompanying caldera collapse. However, the mechanisms of generation, storage and evacuation of the parental silicic magma bodies remain controversial. In this Review, we synthesize field, laboratory and petrological evidence from 13 Quaternary supereruptions to illustrate the range of diversity in these phenomena. Supereruptions can start mildly over weeks to months before escalating into climactic activity, or go into vigorous activity immediately. Individual supereruptions can occupy periods of days to weeks, or be prolonged over decades. The magmatic sources vary from single bodies of magma to multiple magma bodies that are simultaneously or sequentially tapped. In all 13 cases, the crystal-rich (>50–60% crystals), deep roots (>10 km) of the magmatic systems had lifetimes of tens of thousands to hundreds of thousands of years or more. In contrast, the erupted magmas were assembled at shallower depths (4–10 km) on shorter timescales, sometimes within centuries. Geological knowledge of past events, combined with modern geophysical techniques, demonstrate how large silicic caldera volcanoes (that have had past supereruptions) operate today. Future research is particularly needed to better constrain the processes behind modern volcanic unrest and the signals that might herald an impending volcanic eruption, regardless of size.