Stratigraphic unit or tectonic unit?

Abstract: The determination of the characteristics of metamorphic terranes on paleocontinental margins is very important for studying the tectonic evolution. Because of late-stage deformation and metamorphism, the originally different tectonic units have been modified into a seemingly complete set of stratigraphic units, but there are great differences in isotopic age, metamorphic grade, special association between magmatism and strata, and spatial extension, which is the most typical in the Dantazi Group on the northern margin and the Taihua Group on the southern margin of the North China continental nucleus. So the authors suggest that the mapping method of "structure-rock facies complex zone" be used to substitute for the stratigraphic method in metamorphic terranes, which is helpful to determining the tectonic evolution in the area.