Abstract:

This paper deals with palaeontologic characteristics of the main Paleogenedepositional basins in east China.Five assemblages and four evolution phasesof Ostracrda can be summarised.Five fossil assemblages:Upper Oligocene Chinocythere unicuspinata-Dongyingia-Cyprinotus-Cyprois Assemblage.Lower-Middle Oligocene Cyprinotus(Heterocypris)jingheensis-Pinnocypris-Austrocypris-Huabeinia-Chinocythere Assemblage.Upper Eocene Cyprinotus igneus-Echinocypris fabaeformis-Limnocythere jiang-suensis Assemblage.Lower Eocene Sinocypris reticulata-Limnocythere weixianensis-Cypris decaryi Assemblage.Upper Palaeocene Sinocypris funingensis-Eucypris hengyangensis-Parailyocypris changzhouensis Assemblage.Lower Palaeocene Cypridea(Morinina)xindianensis-Porpocypris-Parailyo-cypris taizhouensis Assemblage.Four major evolution phases:1.Meso-Cenozoic mixed fauna phase;2.Sinocypris fauna phase;3.Chinocythere fauna Phase;4.Dongyingia faunaphase.According to the contrast of Ostracod assemblages,a conclusion can bedrawn that the formation of Palaeogene depositional basins took place earlierin South China than in the North.