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华北地块自太古宙形成统一的克拉通之后，于元古宙时期进入伸展张裂构造演化阶段。在华北地块南部，由于地幔物质运动的不均匀性和地幔柱上涌，发生南北向伸展运动，继之形成熊耳裂陷盆地，伴随岩浆侵入－火山喷发活动，产生板内熊耳群火山岩系。在熊耳裂陷盆地中，基底是起伏不平的，呈现出盆－岭构造景观。熊耳群火山岩系由拉斑－钙碱和钙碱－碱性两个岩石系列组成。晚期碱性岩浆活动形成的正长岩和石英二长岩的单颗粒锆石Ｕ－Ｐｂ年龄分别为（１７５０±６５）Ｍａ和（１７３１±２９）Ｍａ，确定熊耳群上限年龄约为１７００Ｍａ。参照中条山区西阳河群下部许山组中锆石Ｕ－Ｐｂ年龄，熊耳群下限年龄约为１８５０Ｍａ
The North China massif has formed a unified craton since the Archean, and entered the stage of extensional Zhang-Zhang tectonic evolution during the Proterozoic. In the southern part of North China block, due to the heterogeneity of mantle material movement and upwelling of mantle plume, the extensional north-south movement occurs, followed by the formation of the bear ear rift basin. With the magmatic intrusive-volcanic eruption, the intra-plate xeritone volcanic series are formed. In the bear ear rift basin, the base is undulating, showing a basin - ridge tectonic landscape. The Xiong’er Group volcanic rocks are composed of two series of rock-caustic soda and caustic-alkaline rocks. The zircon U-Pb ages of single-grain zircons from the late alkaline magmatic activity are 1750 ± 65 Ma and 1731 ± 29 Ma, respectively, confirming that the upper limit of the age of the bear ear group is about 1700 Ma. According to the zircon U-Pb ages of the Xushan Formation in the lower part of the Xiyanghe Group in the Zhongtiao Mountains, the lower limit of the age of the Xiong’er Group is about 1850Ma