卓潘杂岩体是金沙江—哀牢山富碱侵入岩带的重要组成部分,位于兰坪盆地西部.岩体主要由辉长岩、辉石岩及正长岩组成,各岩石的K2O含量为0.96％～7.36％,Na2O含量为0.52％ ～ 6.62％,Na2O+K2O含量为1.98％～8.97％,K2O/Na2O比值介于0.35 ～11.15之间,属于高钾、富碱的钾玄岩系列.岩石中的辉石为透辉石,长石主要为钠长石(An＜5)和正长石,黑云母为镁质黑云母.计算获得辉石的结晶温度范围介于1 070～1 490℃之间.各矿物成分特征表明卓潘杂岩体属于富铁、高氧逸度的岩浆体系,形成于后碰撞的挤压环境向伸展环境转换的构造背景.%The Zhuopan alkaline complex is located in the western Lanping basin and is an important part of the Jinshajiang-Ailaoshan alkali-rich intrusion belt.The Zhuopan alkaline complex is mainly composed of gabbro,pyroxenolite and syenite,and their K2O contents of the whole rock vary from 1.98％ to 8.97％;the Na2O contents are from 0.52％ to 6.62％,the Na2O + K2O contents are from 1.98％ to 8.97％ and the K2O/Na2O ratios change between 0.35 and 11.15,indicating that they belong to the high K,alkali-rich shoshonite series.Electron microprobe analysis(EMPA) indicates that the pyroxene is dominated by the diopside;the feldspar is mainly albite (An ＜ 5) and orthoclase feldspar;and biotite is Mg-biotite in the complex rock.Pyroxene thermometer calculation shows that the crystallization temperature was from 1,070 to 1,490 ℃.According to the geochemical characteristics of the different rocks and minerals,we deduce that the Zhuopan alkaline complex was sourced from a magmatic system with high oxygen fugacity and iron content and formed in a transition tectonic setting changing from post collisional compression to extensional environment.
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