现代地质2017，Vol.31Issue(3)：508-520,13.
内蒙古东乌珠穆沁旗查干敖包花岗岩体时代、成因及地质意义
Ages, Origin and Geological Implications of the Chaganaobao Granite Body in the East Ujimqin Banner, Inner Mongolia
摘要
Abstract
The Chaganaobao pluton in the north of the East Ujimqin Banner,Inner Mongolia can be divided into gray-yellow fine-grained granite unit and gray-yellow medium-fine-grained porphyraceous medium-finegrained two-mica granite unit.The U-Pb weighted average age of the former is (306.4-± 2) Ma,which is the product of Late Carboniferous magmatic activity.The latter has a U-Pb weighted average age of (278.3 ± 2) Ma,which is the product of Early Permian magmatic activity.The two kinds of granites have similar geochemical characteristics.The main elements are all rich in Si,but poor in Ti,Mg,Ca and have a high ratio of alkali/aluminum (NK/A),all of which show obvious negative Eu anomalies.Trace elements are enrichment of Rb,Th,U,K and are low enrichment of P,Zr,Hf,and have a strong loss of Ba,Sr,Ti.Based on the analysis and discussion,we conclude that the Late Carboniferous granite unit and the Early Permian mediumfine-grained porphyraceous granite unit are all the I-S transitional calc-alkaline granite type.The petrochemistry,rock formations,distribution and rocks sources all indicate that the late Late Carboniferous and early Permian granite body of the Chaganaobao were consistent with the product of the Late Paleozoic Central Asia orogenic tectonic setting and transformation period tectonic-magmatic event.关键词
查干敖包/花岗岩体/锆石U-Pb年龄/岩石地球化学/构造背景/东乌珠穆沁旗/内蒙古Key words
Chaganaobao/granite body/zircon U-Pb age/petrochemistry/tectonic setting/the East Ujimqin Banner/Inner Mongolia分类
天文与地球科学引用本文复制引用
程新彬,何付兵,王玮,魏波,徐吉祥,孙永华,方同明,刘振华,尤世娜,刘鸿..内蒙古东乌珠穆沁旗查干敖包花岗岩体时代、成因及地质意义[J].现代地质,2017,31(3):508-520,13.基金项目
中国地质调查局“内蒙古1∶5万巴彦敖包等四幅区域地质调查”项目(基[2010]矿评01-09-04). （基[2010]矿评01-09-04）
