陕西大荔一早更新世哺乳动物群

陕西大荔县洛河下游后河村附近游河组之上黄褐色砂砾层中,发现一个很有意义的动物群.动物群中含有典型的第四纪哺乳动物化石,如似三门马 (Equus cf. sanmeniensis)、平额象 (Archidiskodon planifrons)、奥米加鼢鼠 (Myospalaxomegodon) 和复齿拟鼠兔 (Ochotonoides complicidens) 等.经过对动物群特点、岩相古地理及古气候的分析,并与华北、华南及欧洲同期对比,该动物群在时代上介于狭义泥河湾期与游河期之间,名为后河村期.

AN EARLY PLEISTOCENE MAMMALIAN FAUNA FROM DALI, SHAANXI

An Early Pleistocene mammalian fauna was discovered from yellow sand-bed overlying the green lacustrine deposits of Youhe Formation in the district of Houhe village, Dali, Shaanxi Province during 1978-1984. Because of the existence of Myospalax omegodon and Ochotonoides complicidens and so on, the age of the fauna is considered to be earlier than that of Nihewan fauna and later than that of Youhe fauna, and the mammalian fauna may represent the earliest Pleistocene mammalian fauna in North China. On the analyses of fauna character, lithofacies, palaeogeography and palaeoclimatic, it is necessary that the Early Pleistocene should be divided into two of ages. The early Houhecun represents early Early Pleistocene and late Nihewan marks late Early Pleistocene. That is, the lower boundary between Houhecun and Youhe Formation might be the lower boundary of Quaternary in North China.