【摘要】 通过对银根—额济纳旗盆地苏红图坳陷火山岩进行39Ar-40Ar同位素测年得到该套火山岩年龄值为（105.55±4.03）^112.71±2.06Ma,为早白垩世喷发物。对苏红图火山岩与位于阿尔金断裂周缘的酒西盆地红柳峡火山岩的年龄及地化特征进行了对比研究,认为红柳峡火山岩及苏红图火山岩均为阿尔金—恩格尔乌苏断裂断裂在早白垩世（106¹13 Ma）重新活动的产物,但它们来自于不同幔源区。更为重要的是,这可能说明了从阿尔金断裂开始活动到红柳峡火山岩及苏红图火山岩喷发的这些时间里,阿尔金断裂北东方向的范围至少延伸到了苏红图地区。更多还原

【Abstract】 In the study,the 39Ar-40Ar dating of volcanic rocks of Suhongtu Depression in Yingen-Ejina Qi Basin yielded an age of(105.55±4.03)-(112.71±2.06) Ma,indicating the rocks being the Early Cretaceous eruption products.The volcanic rocks in Suhongtu Depression and in Hongliuxia of Jiuxi Basin are the eruption products of the same period caused by the reactivation of the Altun-Engeerwusu Fault in the Early Cretaceous(106-113 Ma) according to the geochronology,but they might come from different mantle source regions according to their geochemical characteristics.More important,the study suggested that from the beginning of the activation of the Altun Fault to the volcanic eruptions in Suhongtu and Hongliuxia,the Altun Fault had at least extended northeastward to the Suhongtu area.更多还原