Na₂O + K₂O vs. SiO₂ for intra-continental mantle-derived magmas (a). Plots of Ni vs. MgO (b), Cr + Co + Zn + V vs. Ni (c), FeO (d), CaO/Al₂O₃ (e) and CaO vs. Cr (f) in intra-continental basalts with SiO₂ < 52 wt.% and MgO > 4%. The data of intra-continental basaltic magmas are from Yang et al. (2012), Huang et al. (2015), Tian et al. (2016, 2018), Liu et al. (2015), Wang et al. (2016), Li et al. (2017), Su et al. (2017b), Sun et al. (2017), Wang et al. (2017), Cheng et al. (2018).