【摘要】 岩浆补给-混合作用是导致花岗质岩石成分多样性的重要原因，然而目前较少研究涉及晶粥状态下岩浆补给-混合作用的精细过程。本文选择华南晚中生代灵山岩体中心相粗粒斑状花岗岩及其中的闪长质包体和新发现的细粒斑状花岗岩透镜体及其中的细粒正长岩为研究对象，重点分析其斜长石的结构与成分，以刻画花岗质晶粥中岩浆补给-混合作用的精细过程。斜长石的成分与环带结构特征表明，灵山细粒斑状花岗岩、细粒正长岩和闪长质包体均形成于岩浆补给-混合作用过程。首先，补给的中-基性岩浆导致了花岗质晶粥体(粗粒斑状花岗岩)发生了大程度部分熔融与岩浆混合，在晶粥体底部形成了岩浆混合层。随后，岩浆混合层搅动，混合岩浆上升并与晶粥中的高硅易熔矿物或高分异熔体相互作用，最终形成具有强烈混合作用特征的细粒斑状花岗岩。细粒正长岩也经历了类似的岩浆补给-混合过程，只是补给的岩浆更富碱，且岩浆混合程度略低于细粒斑状花岗岩。从混合层脱离出的混合程度低的岩浆，与主体花岗质晶粥相互作用有限的情况下较快冷凝，则结晶形成闪长质包体。灵山晶粥储库岩浆补给-混合作用具有一定规模，输入大量热、富F挥发分和Nb、Ta、Rb等稀有金属元素，促进了花岗岩浆的持续分异演化与稀有金属成矿。更多还原

【Abstract】 The processes of magma recharge and mixing play a crucial role in the compositional diversity of granitic rocks. However,a comprehensive investigation into the intricate processes involved in magma recharge and mixing within a granitic mush remains elusive. This study mainly conducts detailed textural and compositional analyses of plagioclases in the coarse-grained porphyritic granite,its associated dioritic enclaves,and the newly discovered lens-shaped fine-grained porphyritic granite and the fine-grained syenite within it in the Lingshan complex in South China,to elucidate the intricate magma recharge and mixing processes. The compositional zoning of Lingshan plagioclases indicates that both the fine-grained porphyritic granite,fine-grained syenite and dioritic enclaves were formed through magma mixing. Initially,recharged intermediate-mafic magmas triggered extensive partial melting of the granitic mush( coarse-grained porphyritic granite),resulting in a mixing layer at its base. Subsequently,during the stirring of the magma mixing layer,the mixed magmas ascended and interacted with high-Si fusible minerals or highly differentiated melts within the granitic mush,ultimately forming the fine-grained porphyritic granite characterized by intense mixing signatures. The fine-grained syenite underwent a magma recharge and mixing process similar to that of the fine-grained porphyritic granite,but it involved a more alkali-rich recharging magma and exhibited a slightly lower degree of mixing. Dioritic enclaves formed after a low degree mixing magma detached from the mixing layer,and underwent minimal interaction with the host granitic crystal mush. Magma recharge and mixing within the Lingshan mush reservoir operated on a considerable scale,facilitating the sustained differentiation of the granitic magma and rare-metal mineralization by delivering abundant heat,F-rich volatiles,and rare-metal elements( e. g.,Nb,Ta,and Rb).更多还原