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为给夏日哈木矿床成因研究提供新的依据,本文在系统岩心编录的基础上,对该矿床的铬尖晶石进行了研究。薄片鉴定表明,铬尖晶石与橄榄石紧密共生,呈粒状或浑圆状分布于橄榄石和辉石晶体内部。电子探针分析表明,铬尖晶石的Ti O2及Fe2O3含量较低,Cr#值与Mg#值变化范围较大且二者呈负相关关系,包裹于橄榄石中的铬尖晶石具有较高的Cr2O3含量。由铬尖晶石成分推测该矿床母岩浆属于低Ti、高Mg拉斑玄武质岩浆,起源于软流圈地幔。铬尖晶石Fe3+-Cr-Al、Mg#-Cr#图解和矿物岩石组合表明,夏日哈木矿床可能不是形成于岛弧环境,而可能形成于碰撞后的伸展环境。
In order to provide a new basis for the study of the genesis of the summer-harm deposits in the world, based on systematic cataloging of the cores, the chromite spinel in this deposit was studied. Flake identification showed that chrome spinel coexists closely with olivine and is grainy or rounded within the olivine and pyroxene crystals. Electron probe analysis showed that the content of Ti O2 and Fe2O3 in chromium spinel is low, the range of Cr # value and Mg # value is relatively large, and the two are negatively correlated. The chrome spinel encased in olivine High Cr2O3 content. It is inferred from the chromite spinel that the parent magma belongs to the low-Ti and high-Mg tholeiitic magmatic magma originating from asthenospheric mantle. The combination of the chromite spinel Fe3 + -Cr-Al, Mg # Cr # diagrams and the mineral-rock assemblages shows that the summer Ha-Mu ore deposit may not form in the island arc environment but may form after the collision.