Inferred Eclogite-Facies Relics in the Migmatite Unit of the Dabie Block and the Blueschist Unit of the Tongbai Complex, Eastern China Chin-Ho Tsai (Hualien Teachers College); Hanwen Zhou (China University of Geoscience (Wuhan)); Yoshiyuki Iizuka (Academia Sinica (Taipei)) Two new occurrences of metabasites with inferred eclogite-facies relics included in deformed marbles have been recently recognized in the Dabie and Tongbai region. One is garnet metabasite as sheared boudins enclosed within dolomitic marble, which crops out in the migmatite unit of the Dabie block. The other is garnet metabasite as discontinuous pods within deformed marble in the blueschist unit of the southern Tongbai. The Dabie marble contains calcite and dolomite, with accessory phlogopite, quartz, plagioclase, tremolite, and olivine. The mineral assemblages indicate amphibolite-/granulite-facies metamorphism. The included metabasite contains garnet, quartz, hornblende, clinopyroxene, plagioclase, titanite, and rare rutile. Mineral textures indicate that hornblende, sodic plagioclase, clinopyroxene (diopsidic), and titanite are post-peak reaction products. On the basis of reaction textures and mineral compositions, we infer the existence of precursor omphacite (i.e. eclogite-facies assemblage) in the metabasite. Post-collisional migmatization might have caused the amphibolite-/granulite-facies overprinting on the metabasite-marble association. Our new discovery explains the shortage of UHP records in the migmatite unit. The Tongbai metabasite contains garnet, green hornblende, and quartz, with accessory rutile, and relict clinopyroxene. Some garnet grains contain unusually abundant tiny TiO2 precipitates with or without orientation. The host marble contains calcite and accessory white mica, quartz, apatite, relict garnet, and rutile. Although no evidence of UHP metamorphism has yet been identified in these Tongbai rocks, some petrographic features, such as polycrystalline quartz inclusions in garnet (metabasite) and “palisade”-textured quartz (marble), have led to our speculation about a precursor UHP stage. We interpret the metabasite as former eclogite associated with marble, and propose a need to revise the regional tectonic framework.