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通过化石组合和岩性指标分析松辽盆地上白垩统自下而上青山口组—姚家组—嫩江组一段介形类的古生态学。青山口组盐度具有偏咸性、微咸性到半咸性的变化,32个介形类种以栖居于温暖湿润气候带的浅湖微咸水类型占绝对优势,水体清澈安静,有机质丰富,底质为泥等细粒沉积物(个别的为粉砂沉积物),宜于介形类动物群生长且有利于壳体完好保存;其次为生活于半咸水的深湖—半深湖类型,底质为泥。姚家组—嫩江组一段见23个介形类种,栖居于温暖半湿润气候带,以半咸水的深湖、半深湖—浅湖区的类型为主,多泥底,偶见粉砂质底;其次为微咸水的浅湖—三角洲前缘型,泥或粉砂质底;仅3个种生活于温暖湿润的粉砂质底淡水浅湖区。温暖湿润的淡水三角洲分流平原带则难以产出介形类化石。
Paleoecology of the Upper Cretaceous Qiaoshankou Formation - Yaojia Formation - Nenjiang Formation of the Upper Cretaceous in the Songliao Basin was analyzed based on fossil assemblages and lithological indices. The salinity of the Qingshankou Formation is salty, slightly salty to semi-salty. The 32 mesa species dominate the shallow lake brackish water habitat in the warm and humid climate zone. The water body is clear and quiet with rich organic matter , The sediment is fine sediment such as mud (individual silt deposits), should be suitable for the growth of ostracods and is conducive to the preservation of the shell intact; followed by the deep lake in the brackish water - semi-deep lake Type, the sediment is mud. In the first section of Yaojia Formation and Nenjiang Formation, there are 23 types of landforms inhabiting in the warm and semi-humid climate zone, with semi-salt water deep lake, semi-deep lake and shallow lake area as main types, multi-muddy and occasionally silt Followed by brackish water shallow lake - delta front, mud or silty bottom; only three species live in warm and moist silty bottom freshwater shallow lake area. Warm and humid freshwater delta shoal zone is difficult to produce the mesogenic fossils.