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Principles of Petrological Analysis of Igneous Rocks
Published in O.A. Bogatikov, R.F. Fursenko, G.V. Lazareva, E.A. Miloradovskaya, A. Ya, R.E. Sorkina, Magmatism and Geodynamics Terrestrial Magmatism Throughout the Earth’s History, 2020
The calc-alkaline series contains mainly andesite, dacite and rhyolite and usually subordinate amounts of high-Al basalt and andesite-basalt. The SiO2 content varies from 52% to 70%; the groundmass contains hyperstene and pigeonite. There is no trend of enrichment in iron and low Ti content. Cerium-group TREE are more numerous as compared with those in the tholeiite series, and the total REE content is also high. At present, at least two specific series — predominantly low-Mg andesite and less commonly high-Mg boninite — can be recognized within the calc-alkaline series. The boninite series has high chromium and nickel content. The composition of the rock-forming minerals is distinctive, with the concomitant occurrence of four pyroxenes: bronzite, augite, pigeonite and pigeonite-augite; clinoenstatite is rare. The feature of the rocks is the andesitic composition of the volcanic glass in the basic and ultrabasic members of the series.
Scientific ocean drilling in the Australasian region: a review
Published in Australian Journal of Earth Sciences, 2022
Comprehensive geochemical (major and trace elements, mineralogy, radiogenic isotopes, and ages) data have been published for the igneous rocks recovered by Expedition 352 (Li et al., 2019; Reagan et al., 2019; Shervais et al., 2018; Whattam et al., 2020). In combination with rocks recovered from the surface of the trench wall, the equivalence of the IBM forearc section with that of large, stratigraphically complete ophiolites is clear (e.g. Ishizuka et al., 2014). The FAB were generated by seafloor spreading in the earliest stages of arc inception, sourced from prior melt-depleted upper mantle sources without input from the newly created subducted Pacific slab (Reagan et al., 2019; Shervais et al., 2019). The succeeding boninite series rocks were generated in part by slab-derived flux melting of depleted mantle wedge sources.