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Table 2 Igneous-tectonic associations, modified after Wilson (2007)

From: “Volcanism in the Chugoku region: a review for the first UNESCO field school on Geoenvironmental disaster reduction”

 Plate MarginIntra Plate
 ConvergentDivergentIntra OceanicIntra-Continental
Igneous-tectonic associations- Island Arcs
- Continental Arcs
- Young (< 25 Ma) subduction zones
- Mid ocean ridge basalt (MORB)
- Back-arc spreading centres
- Oceanic Islands (OIB)- Continental rift zones
- Continental Intraplate Volcanism
Magma Series- Tholeiitic
- Calk-Alkaline
- Alkaline
- Adakite, HMA
- Tholeiitic- Tholeiitic
- Alkaline
- Tholeiitic
- Alkaline
SiO2 range- basalts and differentiates- basalts- basalts and differentiates- basalts and differentiates
  1. -Alkaline vs Subalkaline rocks. Distinguished within the Total Alkali vs Silica diagram (TAS) but on different discrimination functions (Irvine and Baragar 1971; Miyashiro 1978; LeBas et al. 1986).
  2. -Subalkaline rocks are further distinguished into a Tholeiitic and a Calc-alkaline series by different criteria (Irvine and Baragar 1971; Miyashiro 1974).
  3. -Adakites and High Magnesium Andesites (HMA). Magmas from young, hot subduction zones (e.g. SW-Japan arc) show distinct characteristics in comparison with those from old mature subduction zones (e.g. NE-Japan arc). The difference is related to the thermal structure of the subduction zone and the possibility to directly melt the subducted oceanic lithosphere (Kay 1978; Defant and Drummond 1990). Adakites and associated rock types also occur in other settings where their origin is debated. For a review see Martin et al. (2005).
  4. -I-Type vs. S-Type intrusiva distinguished on the basis of igneous (I) and sedimentary (S) source rocks (Chappell and White 1992)