摘要
华北克拉通是我国早前寒武纪条带状铁建造(BIF)最重要的分布区。近年来大量锆石定年研究表明,华北克拉通BIF形成于始太古代到古元古代早期,但主要为新太古代晚期(2.50～2.55Ga)。最重要的BIF分布于华北克拉通东部的鞍本、冀东和鲁西地区,沉积环境相对稳定是大规模BIF形成的重要条件。华北克拉通新太古代晚期BIF形成的构造环境还不十分清楚,但可能为岛弧构造环境。BIF明显的时代专属性是地质和大气演化的结果。
Early Precambrian banded i （NCC）, such as northern L Daqingshan, Wutai, Luliang, Abundant SHRIMP U-Pb data o in formation age from Paleoarch ron formations （BIFs） are widely iaoning, Anshan-Benxi, western distributed in the North China Craton Liaoning, eastern Hebei, Guyang, Defeng, Zanhuang, Huoqiou, western Shandong, eastern Shandong. btained in recent years indicate that BIFs in the NCC show large variations ean to early Paleoproterozoic, but mainly concentrate in late Neoarhcean （2.55～2.50 Ga）. The most important BIFs occur in Anshan-Benxi, eastern Hebei and western Shandong in the eastern NCC where earlier （〉2.6 Ga） continental basement had been developed. This may suggest that stable environment should be necessary in formation of hugescale BIFs. The late Neoarchean BIFs are considered to be formed in mantle plume or more possibly, arcisland environment. The age distribution of BIFs is mainly due to geological and atmosphere evolution throughout Earth history.
出处
《地质学报》
EI
CAS
CSCD
北大核心
2012年第9期1447-1478,共32页
Acta Geologica Sinica
基金
国家"973"项目(编号2012CB416600)
国土资源部项目(编号1212011120151
1212010811033)资助成果
