Mather Ben R, Müller R Dietmar, Seton Maria, Ruttor Saskia, Nebel Oliver, Mortimer Nick
EarthByte Group, School of Geoscience, The University of Sydney, Sydney, NSW 2006, Australia.
Sydney Informatics Hub, The University of Sydney, Sydney, NSW 2006, Australia.
Sci Adv. 2020 Dec 16;6(51). doi: 10.1126/sciadv.abd0953. Print 2020 Dec.
Long-lived, widespread intraplate volcanism without age progression is one of the most controversial features of plate tectonics. Previously proposed edge-driven convection, asthenospheric shear, and lithospheric detachment fail to explain the ~5000-km-wide intraplate volcanic province from eastern Australia to Zealandia. We model the subducted slab volume over 100 million years and find that slab flux drives volcanic eruption frequency, indicating stimulation of an enriched mantle transition zone reservoir. Volcanic isotope geochemistry allows us to distinguish a high-μ (HIMU) reservoir [>1 billion years (Ga) old] in the slab-poor south, from a northern EM1/EM2 reservoir, reflecting a more recent voluminous influx of oceanic lithosphere into the mantle transition zone. We provide a unified theory linking plate boundary and slab volume reconstructions to upper mantle reservoirs and intraplate volcano geochemistry.
长寿且广泛分布的板内火山活动没有年龄递进，这是板块构造学中最具争议的特征之一。先前提出的边缘驱动对流、软流圈剪切和岩石圈拆离无法解释从澳大利亚东部到西兰迪亚的约5000公里宽的板内火山省。我们对超过1亿年的俯冲板块体积进行建模，发现板块通量驱动火山喷发频率，这表明富集的地幔过渡带储层受到了刺激。火山同位素地球化学使我们能够区分板块贫乏的南部的一个高μ（HIMU）储层[超过10亿年（Ga）历史]和北部的EM1/EM2储层，这反映了近期大量海洋岩石圈流入地幔过渡带。我们提供了一个统一的理论，将板块边界和板块体积重建与上地幔储层及板内火山地球化学联系起来。
