Magma reservoir failure and the onset of caldera collapse at Kīlauea Volcano in 2018.

Autor: Anderson KR; U.S. Geological Survey, California Volcano Observatory, Moffett Field, CA, USA. kranderson@usgs.gov., Johanson IA; U.S. Geological Survey, Hawaiian Volcano Observatory, Hilo, HI, USA., Patrick MR; U.S. Geological Survey, Hawaiian Volcano Observatory, Hilo, HI, USA., Gu M; Department of Statistics and Applied Probability, University of California, Santa Barbara, CA, USA., Segall P; Department of Geophysics, Stanford University, Stanford, CA, USA., Poland MP; U.S. Geological Survey, Cascades Volcano Observatory Vancouver, WA, USA., Montgomery-Brown EK; U.S. Geological Survey, California Volcano Observatory, Moffett Field, CA, USA., Miklius A; U.S. Geological Survey, Hawaiian Volcano Observatory, Hilo, HI, USA.
Jazyk: angličtina
Zdroj: Science (New York, N.Y.) [Science] 2019 Dec 06; Vol. 366 (6470).
DOI: 10.1126/science.aaz1822
Abstrakt: Caldera-forming eruptions are among Earth's most hazardous natural phenomena, yet the architecture of subcaldera magma reservoirs and the conditions that trigger collapse are poorly understood. Observations from the formation of a 0.8-cubic kilometer basaltic caldera at Kīlauea Volcano in 2018 included the draining of an active lava lake, which provided a window into pressure decrease in the reservoir. We show that failure began after <4% of magma was withdrawn from a shallow reservoir beneath the volcano's summit, reducing its internal pressure by ~17 megapascals. Several cubic kilometers of magma were stored in the reservoir, and only a fraction was withdrawn before the end of the eruption. Thus, caldera formation may begin after withdrawal of only small amounts of magma and may end before source reservoirs are completely evacuated.
(Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
Databáze: MEDLINE
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