FURTHER DISCUSSION ON THE METAMORPHIC SEQUENCE OF LIAOHE GROUP

The original rocks of Liaohe Group are dominated by muddy and silty rocks, which experienced greenschist to amphibolite facies metamorphism, resulting in a rich composition of metamorphic minerals. The metamorphic mineral assemblages of different levels are generated at each peak period of metamorphism. They just coexist in space, but have no relationship of time. It cannot be relied on to divide metamorphic stages and episodes, nor be used to make the P-T-t track. In the same mineral assemblage, with sliding reaction and complex response, the minerals reach a balanced coexistence under certain temperature and pressure conditions. The metamorphic degrees of various minerals are the same, while the formation time is simultaneous or not. Some researchers believe that the metamorphic mineral formation sequence is Chl→Bt→ Gt →Stau→And (Ky) →Sill (Cord), which is debatable.