华北克拉通北部地区古-中元古代富碱侵入岩年代学及意义  

Chronology and geological implication of the Paleo-Mesoproterozoic alkaline-rich intrusions belt from the northern part in the North China Craton.

作　　者：任康绪[1] 阎国翰[1] 蔡剑辉[1] 牟保磊[1] 李凤棠[1] 王彦斌[2] 储著银[3] 

机构地区：[1]北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室,北京100871 [2]中国地质科学院地质研究所,北京100037 [3]中国科学院地质与地球物理研究所,北京100029

出　　处：《岩石学报》2006年第2期377-386,共10页Acta Petrologica Sinica

基　　金：国家自然科学基金(40072024;49373170)资助项目。

摘　　要：本文报道华北克拉通北部燕辽三叉裂堑系和辽-吉拗拉谷内一系列古-中元古代富碱侵入岩的锆石U-Pb年龄。这些岩体整体呈近东西向分布,与该地区同期发育的其他非造山球斑花岗岩、斜长岩和大红裕组火山岩都形成于拉张性构造环境,并构成了一条长近千公里的迄今国内外最古老的富碱侵入岩带。该富碱侵入岩带具有东部较老(＞1．8Ga)和西部年轻(1．7Ga左右)的特点,它提供了华北克拉通在1．85～1．70Ga期间处于裂解构造格局的最好证据,丰富了全球性前寒武纪超大陆裂解的研究内容。U-Pb age data on zircons is reported for the Paleo-Mesoproterozoic alkaline-rich intrusions respectively in the Yan-Liao triple-junction aulacogen system and in the Liao-Ji aulacogen of the North China Craton （NCC）. These intrusives, which are approximately distributed along east-west direction, together with other anorogenic rocks in the same period, such as rapakivi granites, anorthosite and the Dahongyu formation volcanic rocks, are formed in the extensional tectonic settings. These alkaline-rich intrusions are distributed near 1000km in length and form an oldest alkaline-rich intrusion belt so far reported in the world. The belt is characteristed by older rocks （〉1.8Ga） in east end of the belt than those in west end （about 1.7Ga）. The Paleo-Mesoproterozoic alkaline-rich intrusion belt is an excellent example to indicate that the Northern part of the NCC was under extending rift system during 1.85-1.70Ga, and also provide a new information for study on Precambrian supercontinent breakup.

关 键 词：年代学 富碱侵入岩带 古-中元古代 华北克拉通 

分 类 号：P597.3[天文地球—地球化学]