华北陆块东南缘蚌埠地区荆山岩体同位素年龄及其地质意义  

THE ISOTOPIC AGE OF THE JINGSHAN INTRUSIVEIN THE BENGBU REGION OF THE SOUTHEASTERN EDGEOF THE NORTH CHINA BLOCK AND ITS GEOLOGICAL IMPLICATIONS

作　　者：邱瑞龙[1] 徐祥[1] 黄德志[1] 

机构地区：[1]安徽地质调查院,安徽合肥230001

出　　处：《安徽地质》1999年第3期161-164,共4页Geology of Anhui

摘　　要：华北陆块东南缘蚌埠地区广泛分布的一套花岗质岩石，长期以来一直被认为是太古代蚌埠期混合花岗岩。笔者通过野外调研和室内鉴定发现，无论是岩石类型组合，岩石结构特征，还是岩体与围岩明显的侵入接触关系，都表明其具有岩浆侵位及分异演化特征。尤其是从荆山黑云母二长花岗岩的黑云母中所获Ａｒ － Ａｒ 同位素年龄数据， 更进一步证明了该地区混合花岗岩为中生代燕山早期岩浆活动的产物。A suit of granite rocks that widely spread in the Bengbu region of the southeastern edge of the North China Block have for a long time been regarded as mixed granites formed in the Bengbu stage of the Archean, which, however, is not supported by the data acquired in the recent years, which indicate that the rocks have characteristics of magmatic intrusion and differential evolution in veiw of either their rock type association and texture or the intrusive contact relationship between them and wall rocks, especially the 40Ar-39Ar isotopic age of biotite from the Jingshan biotite adamellite that definitely demonstrates the existence of magmatic activity of early Yanshanian stage of the Mesozoic in the region

关 键 词：荆山岩体 ⁴⁰Ar/³⁹Ar同位素年龄 燕山期 

分 类 号：P597[天文地球—地球化学]