A mantle-driven surge in magma supply to Kīlauea Volcano during 2003–2007
A mantle-driven surge in magma supply to Kīlauea Volcano during 2003–2007
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DOI：
10.1038/ngeo1426
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发表时间：
2012-04
影响因子：
18.3
通讯作者：
M. Poland;A. Miklius;A. J. Sutton;C. Thornber
中科院分区：
文献类型：
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作者：
M. Poland;A. Miklius;A. J. Sutton;C. Thornber
火山的喷发活动从根本上受岩浆供应速度的控制。在夏威夷的Kī劳埃亚火山，岩浆从地幔内部的源头通过夏威夷热点上升的速度被认为在最近几十年里相对稳定。在这里，我们表明，在2003年至2007年期间，Kī劳厄火山的岩浆供应至少翻了一番，导致喷发活动发生了戏剧性的变化，并形成了新的喷发喷口。供应激增的初步迹象是2003年至2004年期间二氧化碳排放量的增加，再加上利用全球定位系统和干涉合成孔径雷达测量的Kī劳亚峰会的通货膨胀开始。膨胀不仅限于峰顶岩浆储集层，还记录到距离峰顶50 公里，这意味着在该距离上存在一个相连的岩浆系统。我们还记录了二氧化硫排放量的增加，地震活动的加剧，以及喷发熔岩的成分和温度变化。流经和储存在KīLauea内的岩浆体积的增加，加上二氧化碳排放的增加，表明岩浆涌流来自地幔。我们认为，夏威夷热点地区的岩浆供应可以随着时间尺度的不同而变化，二氧化碳排放可能是评估Kī劳厄火山和其他火山岩浆供应变化的有价值的辅助手段。
The eruptive activity of a volcano is fundamentally controlled by the rate of magma supply. At Kīlauea Volcano, Hawai‘i, the rate of magma rising from a source within Earth’s mantle, through the Hawaiian hotspot, was thought to have been relatively steady in recent decades. Here we show that the magma supply to Kīlauea at least doubled during 2003–2007, resulting in dramatic changes in eruptive activity and the formation of new eruptive vents. An initial indication of the surge in supply was an increase in CO2emissions during 2003–2004, combined with the onset of inflation of Kīlauea’s summit, measured using the Global Positioning System and interferometric synthetic aperture radar. Inflation was not limited to the summit magma reservoirs, but was recorded as far as 50 km from the summit, implying the existence of a connected magma system over that distance. We also record increases in SO2emissions, heightened seismicity, and compositional and temperature variations in erupted lavas. The increase in the volume of magma passing through and stored within Kīlauea, coupled with increased CO2emissions, indicate a mantle source for the magma surge. We suggest that magma supply from the Hawaiian hotspot can vary over timescales of years, and that CO2emissions could be a valuable aid for assessing variations in magma supply at Kīlauea and other volcanoes.