The Late-Permian Emeishan mantle plume event caused large-scale flood basalts and related mafic-ultramafic layered mafic intrusions in the inner zone of the Emeishan large igneous province (ELIP). However, the related crustal magma response of this mantle plume event in the inner zone of the ELIP remains poorly understood. In this contribution, we report contemporaneous (~259 Ma) ferrosyenite and A-type granite in the inner zone of the ELIP, and their chronological and geochemical data suggest simultaneous crustal melting at different depths. The ferrosyenites display moderate SiO₂ (60.14 to 63.58 wt%), high Fe₂O₃T (4.28 to 8.52 wt%) and alkaline (Na₂O + K₂O = 10.91 to 12.75 wt%) contents. In combination with their positive zircon ε_Hf(t) values (+1.5 to +12.9), we propose that the ferrosyenites were formed by high temperature melting of Fe-rich refractory juvenile lower crust at H₂O-poor condition, which was induced by underplating of the high-temperature mantle plume. Rhyolite–MELTS modeling results show that ~7% melting of ferrodiorite-like source at ~1120 °C and 8 kbar can produce similar compositions with least evolved ferrosyenite under a relatively dry condition. The Baima granites have high SiO₂ (70.58 to 74.26 wt%) contents and 10000*Ga/Al ratios (3.00 to 3.28), indicating the affinity to A-type granites. Their evolved zircon ε_Hf(t) values (−8.1 to −0.6) indicate an evolved crustal source region. Rcrust modeling indicates that ~9% partial melting of ancient granodiorite-like crustal material under low pressure condition (4 kbar) can produce the observed granitic compositions. Considering the close spatial and temporal relationship between ferrosyenites and A-type granites, we propose that the emplacement of ferrosyenitic magma resulted in low-degree partial melting at a relatively shallow crustal level, responsible for the formation of the A-type granites. In summary, this study highlights the significant impact on crustal magma response to the high-temperature mantle plume event in the inner zone of ELIP.

二叠纪晚期的峨眉山地幔柱事件在峨眉山大火成岩省（ELIP）的内部带引起了大规模的洪水玄武岩和相关的镁铁质-超镁铁质层状镁铁质侵入体。但是，在ELIP内部区域，该地幔柱事件的相关地壳岩浆反应仍然知之甚少。在此贡献中，我们报告了ELIP内部区域同时存在的（约259 Ma）铁镍矿和A型花岗岩，它们的年代和地球化学数据表明，地壳在不同深度同时熔融。铁锰矿显示出适度的SiO ₂（60.14至63.58 wt％），高的Fe ₂ O ₃ T（4.28至8.52 wt％）和碱性（Na ₂ O + K ₂O ＝ 10.91至12.75重量％含量。与ε其正锆石组合_的Hf（t）值（1.5至12.9），我们建议ferrosyenites由富Fe耐火少年下地壳高温熔化处于H形成₂ O形条件很差，这是诱导通过高温地幔柱的底部电镀。流纹岩-MELTS模型的结果表明，在相对干燥的条件下，〜1120°C和8 kbar时，约有7％的铁闪长石状源融化，可以生成类似的成分，且析出的亚铁矿最少。白马花岗岩具有较高的SiO ₂（70.58至74.26 wt％）含量和10000 * Ga / Al比（3.00至3.28），表明对A型花岗岩具有亲和力。他们演化出的锆石_εHf（t）值（-8.1至-0.6）表示地壳源区的演化。地壳模型表明，在低压条件下（4 kbar），古老的花岗石样地壳材料约9％的部分熔融会产生观察到的花岗石成分。考虑到铁素体岩与A型花岗岩之间的紧密时空关系，我们认为铁素体铁矿岩浆的沉积导致了地壳水平相对较低的低度部分熔融，这是造成A型花岗岩形成的原因。总而言之，这项研究强调了ELIP内部区域对地幔岩浆对高温地幔羽流事件的重大影响。