据悉,中地壳岩浆域是许多玄武岩喷发的发生地。单次喷发产生的熔岩在化学上往往是均匀的,表明它们来自单个混合良好的岩浆储层。
研究人员对2023-2024年冰岛Svartsengi火山系统Sundhnúksgígar火山的喷发产物,进行了详细的采样和地球化学表征,提供了在高时空分辨率下观察中地壳岩浆域行为的机会。
研究人员在2023年12月、2024年1月、2月和3月至5月的喷发产物中,观察到大量地幔衍生的地球化学变化,证明喷发来自多个岩浆储层,其中矿物—熔体平衡压力位于中地壳。中地壳岩浆域中地球化学非均质性的异常存在,揭示了中地壳岩浆域的动态性和复杂性。
附:英文原文
Title: A dynamic mid-crustal magma domain revealed by the 2023 to 2024 Sundhnúksgígar eruptions, Iceland
Author: Simon W. Matthews, Alberto Caracciolo, Enik Bali, Smundur Halldórsson, Olgeir Sigmarsson, Guemundur Guefinnsson, Gro B. M. Pedersen, Jóhann Gunnarsson Robin, Edward W. Marshall, Araksan A. Aden, Bryndís Yr Gísladóttir, Chantal Bosq, Delphine Auclair, Heini Merrill, Nicolas Levillayer, Nomi Lw, Rebekka Hlín Rúnarsdóttir, Sóley M. Johnson, Sveinbjrn Steintórsson, Vincent Drouin
Issue&Volume: 2024-09-26
Abstract: Mid-crustal magma domains are the source of many basaltic eruptions. Lavas from individual eruptions are often chemically homogeneous, suggesting they derive from single well-mixed magma reservoirs. The 2023 to 2024 eruptions at Sundhnúksgígar in the Svartsengi volcanic system, Iceland, provide an opportunity to observe the behavior of a mid-crustal magma domain at high spatial and temporal resolution by detailed sampling and geochemical characterization. We observed substantial mantle-derived geochemical variability in the products erupted in the first hours of the December 2023, January, February, and March-May 2024 eruptions, indicating the eruptions derived from multiple magma reservoirs, which mineral-melt equilibration pressures place in the mid-crust. The unusual presence of geochemical heterogeneity in the mid-crustal magma domain provides an insight into how dynamic and complex mid-crustal magma domains can be.
DOI: adp8778