Formation Age of the Sujiagou Komatiites in Western Shandong: Further Constraints from SHRIMP U-Pb Zircon Dating on Granitic Dykes  

作　　者：WAN Yusheng DONG Chunyan XIE Hangqian WANG Shijin 

机构地区：[1]Beijing SHRIMP Center,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China [2]Shandong Geological Survey Institute,Jinan 250013,China

出　　处：《Acta Geologica Sinica(English Edition)》2020年第4期877-883,共7页地质学报（英文版）

基　　金：financially supported by the Key Program of the Ministry of Land and Resources of China(DD20190370,DD20190009,DD20190358,DD20190003)。

摘　　要：Komatiites are presented as direct evidence for higher mantle temperatures during the Archean. In the North China Craton, komatiites with spinifex structure have been identified only at one locality, i.e. the Sujiagou area, western Shandong. They were considered as formed during the early Neoarchean mainly based on their association with supracrustal rocks considered to be that age. This study carried out SHRIMP U-Pb zircon dating on metamorphosed trondhjemitic and monzogranitic dykes intruding the Sujiagou komatiites, and they have magmatic zircon ages of 2592 ± 12 Ma and 2586 ± 13 Ma respectively. This provides direct evidence that the komatiites formed during the early Neoarchean.

关 键 词：granitic dyke SHRIMP U-Pb zircon dating Sujiagou komatiite Neoarchean western Shandong 

分 类 号：P597.3[天文地球—地球化学] P588.121[天文地球—地质学]