内蒙古哈多河——阿尔本格勒地区花岗岩年代学及其地质意义

对哈多河-阿尔本格勒地区二叠纪花岗岩进行年代学研究，获得花岗岩、花岗斑岩锆石U-Pb SHRIMP年龄分别为133.2±1.7 Ma和127.0±2.0 Ma，为早白垩世.岩石化学研究表明，花岗岩、花岗斑岩均为钙碱性岩石，为S型花岗岩.岩石稀土元素分馏较为彻底，无明显的铕异常，与区域内典型二叠纪花岗岩（SI型）没有明显区别，表明在燕山晚期该地区具有碰撞造山晚期的复杂构造背景，暗示自华力西期至燕山晚期经历了多期次的碰撞造山作用，岩浆活动与古亚洲洋构造域转换、叠加滨太平洋构造域有关.

CHRONOLOGY AND ITS GEOLOGICAL IMPLICATION OF THE GRANITES IN HADUOHE-AERBENGELE AREA, INNER MONGOLIA

Geochronogic study on the previously decided Permian granites in Haduohe-Aerbengele area,Inner Mongolia obtains the U-Pb SHRIMP zircon ages of 133.2±1.7 Ma and 127.0±2.0 Ma for granite and granite-porphyry,respectively, suggesting a Cretaceous age.The lithogeochemical study shows that both the granite and granite-porphyry are calc-alkaline, belonging to S-type granite.The rare earth elements are well fractionated,without significant Eu anomaly.The rocks present no evident differences to the typical granite(SI-type)in the region,showing a complex tectonic setting of late collisionorogeny during Late Yanshanian stage.Multiple collision-orogeny movements took place from Variscan to Late Yanshanian in the region.The magmatic activities are related to the transition of Paleo-Asia tectonic domain and the superposition of marginal-Pacific tectonic domain.