内蒙古海拉尔盆地南部地区晚白垩世青元岗组介形类

内蒙古海拉尔盆地南部探井青元岗组红色碎屑岩中发现较丰富的介形类化石，即下段的Ahanicypris obesa-Talicypridea triangulata组合和上段的Chinocypridea augusta-Talicypridea qingyuangangensis组合，这些介形类化石地方性色彩强烈，表现为以具冠状壳喙类型的Ahanicypris，Talicypridea，Chinocypridea和网纹发育的Harbinia等属繁盛为特征，反映了中国东北地区晚白垩世晚期介形类动物群面貌。根据介形类化石组合特征及其分布规律，可以与松辽盆地晚白垩世四方台组的介形类动物群对比，时代为晚白垩世Maastrichtian期。

OSTRACODA FROM THE QINGYUANGANG FORMATION IN THE SOUTHERN HAILAER BASIN, Nei MONGOL

Abundant Ostracods have been found from the red clastic rocks of the Qingyuangang Formation, the wells of Beier Depression and Wuerxun Depression, southern Hailaer Basin in Inner Mongolia Autonomous Region. Based on the composition and distribution of these Ostracoda species, two Ostracoda assemblages have been classified: Altanicypris obesa-Talicypridea turgida assemblage (lower member) and Chinocypridea augusta-Talicypridea qingyuangangensis assemblage (upper member). These fossils mainly consist of Altanicypris,Talicypridea, Chinocypridea with cristid and Harbinia with reticulation, and are characterized by the strong endemic color, representing the late stage of Late Cretaceous fossil ostracoda fauna in Northeast China. These Ostracoda assemblages may be correlated with that of the Sifangtai Formation of Songliao Basin, indicating their Maastrichtian age, Late Cretaceous.