地质科学2026，Vol.61Issue(2)：328-342,15.DOI:10.12017/dzkx.2026.024
华北克拉通北缘下白垩统张家口组A型流纹岩的发现及地质意义
Discovery of A-type rhyolite in the Lower Cretaceous Zhangjiakou Formation at the northern margin of the North China Craton and its geological significance
摘要
Abstract
Previous studies have shown divergent views on the tectonic setting of the volcanic rocks in the Zhangjiakou Formation,and detailed research on the relationship between these volcanic rocks and the destruction of the North China Craton(NCC)has not been conducted.In this study,we conducted comprehensive geological,petrological,geochronological,and geochemical investigations on the A-type rhyolites discovered for the first time in the upper Zhangjiakou Formation in the Zhangjiakou area,and further analyzed their petrogenesis and formation environment.LA-ICP-MS zircon U-Pb dating yielded an age of 138.4±1.3 Ma(n=30,MSWD=0.84),indicating an Early Cretaceous formation.The rocks are characterized by high silica(SiO2=69.94％～73.35％),high alkalinity(Na2O+K2O=10.13％～10.71％),low contents of MgO,CaO,TiO2,and high Ga/Al ratios.The rhyolites at the top of the Zhangjiakou Formation belong to the A1-type granites.They were formed in a high-temperature,low-pressure intraplate extensional environment,and originated from the partial melting of a thinned felsic middle to lower crust.Based on previous research findings,it is proposed that the A-type rhyolite at the top of the Zhangjiakou Formation represents a geological response to the tectonic regime transition of the North China Craton in northern Hebei,marking the onset of the destruction of the North China Craton.关键词
张家口地区/张家口组/A型流纹岩/板内拉张/克拉通破坏Key words
Zhangjiakou area/Zhangjiakou Formation/A-type rhyolite/Intraplate extension/Cratonic destruction分类
天文与地球科学引用本文复制引用
陈圆圆,段先乐,白春东,田粉英,潘志民,薛鹏远..华北克拉通北缘下白垩统张家口组A型流纹岩的发现及地质意义[J].地质科学,2026,61(2):328-342,15.基金项目
河北省地质勘查专项资金项目(编号:4540401YBNVVG)资助 （编号:4540401YBNVVG）
