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位于东大别山北缘的姚河岩体是最近确定的中侏罗世石英二长岩体，角闪石４０Ａｒ３９Ａｒ法定年为１５５．８Ｍａ，用角闪石压力计法得出结晶压力为（２．６５±０．５）×１０２ＭＰａ，结晶定位深度约９ｋｍ。岩体北缘发育的ＮＥ倾的糜棱岩带是磨子潭晓天断裂韧性剪切的结果。对剪切带中宏观标志及显微、超显微构造研究表明，该断裂自中侏罗世之后主要表现为上盘向ＮＥ方向下滑的正断层，两盘垂直差异隆升达９ｋｍ。结合区域构造及深部资料分析显示，东大别造山带并不具有“翻花状”双侧造山链特点。
The Yaohe pluton located in the northern margin of the Eastern Dabie Mountains is a recently identified middle-Jurassic quartz monzogranite. The 40Ar-39Ar amphibole was dated at 155.8Ma for the amphibole, and the crystal pressure was calculated using the amphibole manometer (2). 65 ± 0.5) × 102MPa, crystal positioning depth of about 9km. The NE mylonite zone developed on the northern margin of the rock mass is the result of the ductile shearing of the Mozi Lake-Xiaotian Fracture. The study on macroscopic sign and microstructure and microstructure of the shear zone show that the fault mainly appears as a normal fault with a dip in the NE direction since the middle Jurassic, and the vertical difference between the two plates is up to 9 km. According to regional tectonics and deep data analysis, the East Dabie orogenic belt does not have the characteristics of “fan-shaped” bilateral orogenic belt.