广州龙归盆地古新世介形类动物群

PALEOCENE OSTRACOD FAUNA FROM THE LONGGUI BASIN OF GUANGZHOU,CHINA

广州龙归盆地古新世介形类化石全部来自全取芯钻井剖面,据42口钻井1000个样品统计,发现介形类16属40种,本文描述其中15属39种。龙归盆地古新世介形类动物群以Cypris,Sinocypris,Cyprois,Li mnocythere四属分布最广、最常见,归属Sinocypris动物群,据其纵向分布规律,划分3个化石带,自下而上为:Ⅰ.Cypris con-cina带;Ⅱ.Sinocypris curtovata带;Ⅲ.Cyprois reniformis带。作者认为Ⅰ带的莘庄村组的时代属古新世早期,Ⅱ带的(土布)心组为古新世中期,Ⅲ带的宝月组为古新世晚期。

Paleocene ostracod Sinocypris fauna from the Longui Basin is characterized by Cypris,Sinocypris,Cyprois and Limnocythere.A thousand samples are collected from the 42 whole coring wells.Totally 40 ostracod species in 16 genera have been recognized,and out of which 39 species in 15 genera have been described in this paper.Three biozones are also recognized：1）the Early Paleocene Cypris concina Zone from the Xinzhuangcun Formation;2）the Middle Paleocene Sinocypris curtovata Zone from the Buxin Formation;and 3）the Late Paleocene Cyprois reniformis Zone from the Baoyue Formation.