含叶肢介：Euestheria complanata等；介形类：Darwinula sarytirmenensis，D. cf. magna，Metacypris caneiformis，Djungarica sp.等；轮藻：Aclistochara lufengensis，A. Yunnanensis，A. Nuguishanensis，Stellatochara sublavis等及腹足类等化石。为湖相沉积。整合于新河组之上；不整合于河口群之下。厚504米。