Path of uhpm consists of two curves , i . e . , a barrette - like curve reflecting the process of cold slab subduction and exhumation cold overthrusting , and a crescent curve representing the thermal exhumation after slab breakoff 軌跡由兩部分組成,即反映板片冷俯沖冷折返過(guò)程的發(fā)夾狀曲線和指示板片斷離拆沉熱折返過(guò)程的新月形曲線。