喇嘛苏铜矿区中酸性岩体的皮科克指数、里特曼指数、赖特指数,均指示其中酸性岩体属于钙碱性岩系的范围;分异指数平均值为77.57,说明岩体的分异演化程度较为彻底;固结指数平均值为12.01,显示出岩体的岩浆分异程度较高;长英指数和铁镁指数均反映岩体的分离结晶作用程度中等.在MF-FL分异趋势图上,样品点基本呈连续分布,说明岩体的演化是连续的;在w(Na2O) ω(K2O)关系图上多数样品点落入I型花岗岩区域,可以认为本区花岗岩应为I型花岗岩.岩体的TiO2含量平均为w(TiO2)=0.28％,远低于中国及世界同类岩石;在戈蒂尼指数与里特曼指数对数值的关系图上,几乎所有的样品点均落在消减带火山岩区,由此可以推断,本区斑岩体应形成于与俯冲作用有关的消减带上.在多阳离子的R1-R2关系图中,多数样品点落在地壳熔融花岗岩-同碰撞的花岗岩区,少数样品点落在其它区域,这说明了岩浆在演化过程中同化混染了围岩.%Peacock index,Rittmann index and Wright index of the acid-intermediate intrusive bodies in Lamasu copper deposit all indicate that the acid-intermediate intrusive bodies in this area belong to calc-alkalic rock series.The average of differentiation index is 77.57 showing their relatively complete differenti-ation evolution;the average of solidification index is 12.01 showing relatively high magmatic differentiation;the average of felsic index is 69.96 and mafic index 61.98 showing the medium degree of fractional crystallization.On MF vs FL differentiation trend chart,distribution of sample point basically is continuous illustrating their continuous evolution.Most sample points on Na2O vs K2O relational diagram fall into the area of I-type granite reflecting that the intrusive bodies are I-type granite.The average content of TiO2 of the intrusive bodies are 0.28％ far below those of the same kind of rocks in other areas of China and other places of the World.On the relational chart of lgτ-lgσ,almost all of the sample points fall into the area of volcanic rock of subduction zone.All this indicates that the intrusive bodies should be formed in subduction zone and they related with subduction process.On the relational chart of R1 vs R2,most of the sample points fall into the area of crustal molten granite and syn-collisional granite,and a few sample pointsl into other areas illustrating assimilation and blending with country rock during the evolution of magama.
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