摘要
对中祁连地块东段西宁西部近Ｓ－Ｎ向展布的元古宙花岗岩带地质地球化学和年代学研究表明：它侵位于元古宙基底中浅变质岩系湟源群中，具有同碰撞Ｓ型花岗岩的性质；（９１７±１２）Ｍａ的单颗粒锆石Ｕ－Ｐｂ年龄记录了其侵位的时代为新元古宙晋宁期，这一新元古宙晋宁期碰撞型花岗岩带具有重要的地质意义。
The Proterozoic granite belt emplaced into the Huangyuan Group -a medium-and low-grade metamorphic series of the Proterozoic basement in the eastern central Qilian massif extends in a N S direction.Its geochemical features indicate that it is a syn_collisional S_type granite belt. (917±12) Ma of single_grain zircon U_Pb age constrains its emplacement age. From above it is suggested that the easten central Qilian massif had undergone Jinningian collisional orogenesis. Finally the authors discuss the geological implication of the Proterozoic syn_collisional granite belt in the easten central Qilian massif.
关键词
中祁连地块
新元古宙
碰撞型
花岗岩
地质意义
eastern central Qilian massif Neoproterozoic syn_collisional granite Jinningian collisional zone N_S trending structure
