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晓天—磨子潭断裂带是大别造山带非常重要的韧性剪切带之一,叠加在北大别灰色片麻岩之上。通过其构造几何学、运动学的研究表明:晓天—磨子潭韧性剪切带具有管壁状弯曲的几何学特征,运动学方式为沿NWW—SEE向近水平左旋剪切。地质温压计和变形矿物动态重结晶型式揭示了剪切带变形温度约618.2℃,地质压力约0.7GPa,相当于中下地壳环境。据此推测大别造山带曾上覆一管状背形韧性剪切层(大部分现已被剥蚀),晓天—磨子潭剪切带为其北界部分;造山带中下地壳物质曾发生近平行造山带走向的侧向流动。。
Xiaotian-Mozitan fault zone is one of the most important ductile shear zones in the Dabie orogen, superimposed on the North Dabie gray gneiss. Through its structural geometry, kinematic studies show that the Xiaotian-Mozi Tan ductile shear zone has the geometric characteristics of tubular wall-like bending, and the kinematic mode is a left-lateral shear near NWW-SEE. The dynamic recrystallization patterns of geothermometers and deformed minerals reveal that the deformation temperature of shear zone is about 618.2 ℃ and the geological pressure is about 0.7GPa, which is equivalent to the middle and lower crustal environment. Based on this, it is speculated that the Dabie orogenic belt had been overlaid with a tubular dorsal-ductile shear layer (most of which had been denuded) and the Xiaotian-Moziitan shear zone was part of its northern boundary. The middle and lower crustal material of the orogenic belt had occurred Lateral flow of nearly parallel orogenic belts. .