【摘要】 金厂沟梁金矿区中与成矿伴生的暗色脉岩主要是细晶闪长岩石英闪长岩、闪长玢岩英安斑岩类。细晶闪长岩石英闪长岩的ALK值为5.47%~5.88%,K2O/Na2O值为0.455~0.496,属钙碱性岩系,并具有Ⅱ型Adakite岩的性质;闪长玢岩英安斑岩的ALK值为7.83%~8.28%,K2O/Na2O值为1.100~1.747,属粗安岩系。元素地球化学特征显示:细晶闪长岩石英闪长岩的岩浆源于富集地幔或洋壳俯冲脱水交代的下地壳,地壳增厚过程产生并就位;闪长玢岩英安斑岩类的岩浆就位相对晚,来源具有上地壳性质或被地壳物质强烈混染,地壳减薄过程形成;这种特征暗示金厂沟梁金矿形成的地球动力学背景是在地壳挤压增厚转化为伸展减薄过程。更多还原

【Abstract】 The dark dikes associated with mineralization in the Jinchanggouliang mine area,are mostly fine diorite-quartz diorites and diorite porphyrite-dacite porphyries.The ALK of the fine diorite-quartz diorites is 5.47%⁵.88%,ratio of K₂O/Na₂O is 0.455⁰.496.Therefore,it belongs to calc-alkalic rock series and shows the characters of Ⅱ-type Adakite;The ALK of dioritic porphyrite-dacite porphyries is 7.83%⁸.28%,ratio of K₂O/Na₂O is 1.100¹.747,belonging to shoshonitic rock series.The characteristics of elements shows that magma of fine diorite-quartz diorites derived from the enriched mantle or lower crust undergone ocean crust subducting and dehydrating,and was formed and emplaced in the process of crust growth.The magma of dioritic porphyrite-dacitic porphyries emplaced relatively late,it might derive from upper crust or undergo intensive contamination of crustal materials,and was formed in the proces of crust thining.These characteristics suggest that the geodynamics background of the Jinchanggouliang gold deposit formation is the transition process from compression to extension.更多还原