安徽月山岩体地球化学特征及成因机理分析

通过对长江中下游地区具代表性的大型矽卜岩－热液脉型铜（铁）、金、多金属矿田中成矿岩体－月山岩体的地质地球化学特征及其成因制约与反演讨论，认为该岩体为深源的碱性玄武质岩浆经过结晶分异和同化混染联合作用（AFC过程）形成的，其中，幔源物质约占70％，同化的壳源物质占30％。这种开放岩浆系统的形成与演化对于该区金属矿床成矿流体系统的形成与演化具有极其重要的意义。

A Discussion on Petrological Characteristics and Genesis of Yueshan Intrusion,Anhui Province

Yueshan ore field is a typical skarn hydrothermal type of Cu (Fe), Au polymetallic ore field in the mineralisation belt of the Middle and Lower reaches of the Yangtze River area. Copper gold deposits in this ore field have close relationship with the Yueshan intrusion. The intrusion consists of diorites, quartz diorites and quartz monzonitic diorites. The geological and geochemical characteristics, especially the petrochemistry, REE, trace elements and Pb, Sr, Nd, O isotope geochemistry of this intrusion, as well as geochemical modeling of its petrogenetic process, are discussed. The results show that the Yueshan intrusion is a MC type granite with 70% of mantle derived material and 30% of crust derived material. It was formed by the process of combined wall rock assimilation of the crustal material and fractional crystallization of the mantle derived alkaline basalt. An open magmatic system of the Yueshan dioritic body is essential to formation and evolution for the ore forming fluid of the metallic ore deposits in this field.