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赣南—粤北中生代晚期存在上、中、下3个不同时代的火山岩系,其中上火山岩系称为版石群。根据岩性岩相特征,版石群可进一步划分为两个岩组:下岩组称为合水组,以砾岩、砂岩、页岩等沉积岩为主、夹火山岩,代表火山活动初始期的产物;上岩组称为优胜组,岩性为流纹岩、流纹质凝灰岩、熔结凝灰岩,代表火山活动喷发期的产物。长塘盆地优胜组熔结凝灰岩全岩RbSr等时线年龄为89.5Ma;仁差盆地优胜组流纹岩全岩RbSr等时线年龄为91.9～94Ma,熔结凝灰岩锆石UPb法年龄为86.5Ma,次流纹斑岩锆石UPb法年龄为93.5Ma;菖蒲盆地优胜组流纹岩全岩RbSr等时线年龄为104Ma;版石盆地优胜组流纹岩全岩RbSr等时线年龄为72.2Ma,全岩KAr法年龄为77.6Ma,可见版石群优胜组的地质时代为早白垩世晚期—晚白垩世早期。另外,合水组的生物化石反映出早白垩世的特征,因此,将版石群置于早白垩世—晚白垩世早期是可信的。
Gannan - northern Guangdong in the late Mesozoic there, the middle and lower three different age volcanic rock series, which is called the rock group of volcanic rocks. According to the characteristics of lithology and lithofacies, the lithofacies can be further divided into two groups: the lower group is called the Heishui Formation, and the sedimentary rocks are mainly composed of conglomerate, sandstone and shale, and the volcanic rocks are sandwiched between them, representing the initial stage of volcanic activities Product; the rock group known as the winning group, rhyolite rhyolite, rhyolitic tuff, melted tuff, on behalf of volcanic activity eruption of the product. The RbSr isochron age of the whole crust in the Yingsheng Formation of the Jiantang Formation in the Changngtang Basin is 89.5Ma. The RbSr isochron age is 91.9-94Ma in the Yinsheng Rim Formation in the Yanan Basin and is 86.5 Ma The RbSr isochron age of the rhyolite in the Yusheng Formation in the Calam area is 104 Ma. The RbSr isochron age of the rhyolite in the Yousheng formation in Banshu Basin is 72.2 Ma , The whole rock KAr method is 77.6Ma in age, showing that the geologic age of the Progression Group of Plateau Group is from Early Cretaceous to Early Cretaceous. In addition, the Hokkaido biofuels reflect the characteristics of the Early Cretaceous, and therefore, it is plausible to locate the lithofacies in the Early Cretaceous-Early Cretaceous.