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川西义敦岛弧碰撞造山带北段雀儿山复式花岗杂岩体的年代学和全岩地球化学研究表明,雀儿山杂岩体主要由花岗闪长岩、二长花岗岩和正长花岗岩组成。锆石LA--ICP--MS U--Pb测年结果显示,该岩体中的花岗闪长岩形成时代为晚三叠世(224±3 Ma),二长花岗岩则形成于早白垩世(102±1 Ma)。地球化学数据表明,晚三叠世花岗闪长岩为火山弧岩石序列,形成环境为碰撞前俯冲环境;早白垩世二长花岗岩和正长花岗岩为后碰撞岩石序列,形成于造山期后板内或陆内环境。结合区域地质资料,认为雀儿山杂岩体为印支期—燕山期义敦岛弧碰撞造山带经历俯冲--碰撞--隆升过程中的产物。
The chronology and whole-rock geochemistry of the Queshan complex granodiorite complex in the northern section of the Yudun Island arc collision orogenic belt in western Sichuan show that the Que’eshan complex mainly consists of granodiorite, monzogranite and granite composition. The results of zircon LA - ICP - MS U - Pb dating show that the granodiorites in the pluton were formed in the Late Triassic (224 ± 3 Ma) and the two long granites were formed in the Early Cretaceous World (102 ± 1 Ma). The geochemical data show that the Late Triassic granodiorite is a volcanic arc rock sequence and formed in a pre-collision subduction environment. Early Cretaceous monzogranite and orthoclase granite are post-collisional rock sequences that were formed in the posterior orogeny plate Or inland environment. Combined with the regional geological data, it is concluded that the Que’eshan complex is the product of the Indosinian-Yanshan Period, the Yudash island arc collision orogenic belt undergoing subduction-collision-uplift.