中国地质2013，Vol.40Issue(1)：232-247,16.
大兴安岭查巴奇地区中生代侵入岩岩石地球化学特征及构造背景
The petrogeochemical characteristics and tectonic setting of Mesozoic intrusive rocks in Chabaqi area of the Da Hinggan Mountains
摘要
Abstract
The Mesozoic intrusive rocks in Chabaqi area are located in the west of Nenjiang fault zone, and the east side of the study area is the joint between apophysis and graben basin. Hence the study of the structure of the study area can provide the information for the orogenic uplift of the Da Hinggan Mountains. The result of SHRIMP U-Pb zircon dating shows that the intrusive rocks were mainly formed in the early Jurassic and late Jurassic period, and the petrogeochemical characteristics show that the intrusive rocks are high-potassium and Si-saturated rocks, belonging to calc-alkaline series. Discrimination diagrams show that the intrusive rocks belong to Ⅰ-type granite of crust-mantle miscibility,and they were formed in a prolonged stable environment but under different formation conditions. The early Jurassic quartz diorite and tonalite have the characteristics of extrusion type, so that they should be formed in a relatively high pressure environment, whereas the late Jurassic monzonitic granites belong to the transition type of extension -extrusion, and hence they should be formed in a high differentiation environment of relative low pressure. The spatial and temporal granite evolution heterogeneity was probably existent in the formation process. Therefore, the relationship between the formation of Jurassic granites and the thickness of the earth's crust can serve as the supporting evidence for the thinning of the earth's crust and lithosphere as well as the stretching orogenic process of the Da Hinggan Mountains.关键词
中生代侵入岩/构造背景/大兴安岭/岩石地球化学特征Key words
Mesozoic intrusive rocks/tectonic setting/Da Hinggan Mountains,petrogeochemical characteristics分类
天文与地球科学引用本文复制引用
戴慧敏,杨忠芳,马振东,宫传东..大兴安岭查巴奇地区中生代侵入岩岩石地球化学特征及构造背景[J].中国地质,2013,40(1):232-247,16.基金项目
中国地质调查局矿调项目"内蒙古查巴奇地区矿产远景调查"(矿调[2004]10-2号)资助. （矿调[2004]10-2号）
