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以商麻断裂为界,大别造山带分为东段和西段,西大别造山带是连接桐柏造山带和大别造山带的纽带.通过对几何学和运动学以及变质环境的研究表明:西大别造山带的形态为一个枢纽向西倾伏的巨型背形构造,且有圈层结构,层间存在滑脱面.西大别地区至少存在着3期构造变形,第一期是南北边界剪切带的形成,第二期是层间滑脱面和榴辉岩透镜体的形成,第三期是晚期的岩体侵入.应力场的统计结果可知,西大别造山带主要受到近南北方向的挤压,统计结果真实地记录了西大别造山带形成时的古应力状态,对应着3期变形的第一期.有限应变测量结果显示,从北向南岩石的变形强度存在着:强变形带→弱变形带→强变形带→弱变形带→强变形带这种强弱变形带交替出现的规律.通过白云母Ti温度计以及多硅白云母压力计结果显示西大别造山带中新县—红安地区岩石的变质条件为T=450℃～620℃,P=1.0～1.6GPa,属于高压蓝片岩相到榴辉岩相.“,”The Qinling-Dabie orogenic belt is formed by collision between Yangtze Craton and North China block.By taking the Shangcheng-Macheng fault as the boundary,the Dabie orogenic belt is divided into east part and west part.The West Dabie orogenic belt is the link between Tongbai orogenic belt and Dabie orogenic belt.The geometry,kinematics and metamorphic environment research show that the West Dabie orogenic belt is a giant antiformal structure in the form with west plunging hinge and there is detachment surface between layer structures.Structural analysis indicated that there are at least three stages of deformation in West Dabie orogenic belt.The first phase is the formation of the boundary shear zones.The second phase is the formation of detachment surface and eclogite lens.The third period is intrusion of late rock mass.The statistical results of stress field suggests the West Dabie orogenic belt is mainly affected by NS direction compressional stress,which truthfully recorded the ancient stress state of the West Dabie orogenic belt.Finite strain measurement results show that from north to south,the deformation intensity of the rock has the variation law with strong deformation zone→ weak deformation zone→strong deformation zone→weak deformation zone→strong deformation zone.The Ti-in-muscovite thermometers and the phengite manometers results show that the metamorphic conditions of the West Dabie orogenic belt are T =450 ℃～ 620 ℃,P =1.0～1.6 GPa,which belongs to the blue schist facies to the eclogite facies.