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自 2 0世纪 60年代 ,陕西蓝田地区就以连续的晚新生代地层及丰富的哺乳动物化石而成为研究中国晚新生代哺乳动物与地层划分对比的经典地区之一。李传夔等 ( 1 984)根据灞河组发现的哺乳动物化石建立了灞河期 ,并与欧洲的Vallesian期对比。邱占祥等( 1 990 ,1 995)认为化石证据不充分 ,而将其与保德期合并。近年来 ,黄土高原三趾马红粘土大量的年代学资料表明 ,红粘土沉积最早可能开始于约 8Ma前。因此 ,狭义的保德期可能只代表了晚中新世晚期 ,晚中新世哺乳动物分期的再划分问题又重新被提出。自 1 997年以来 ,我们课题组在蓝田地区共发现 52个化石地点 ,其中的 2 6个含有哺乳动物化石 ,大哺乳动物化石标本共计 1 666件。经过详细野外地层测量 ,绘制了综合地层剖面 ,并将主要含哺乳动物化石的地点对比标定到综合地层剖面上。经过对各门类化石的初步研究 ,以及对已有化石材料的初步修订 ,到目前为止 ,陕西蓝田灞河组共计发现哺乳动物化石 45种 ,蓝田组 2 0种。新的化石证据表明 ,灞河组发现的哺乳动物化石组合完全不同于典型意义上的保德三趾马动物群。大哺乳动物化石以灞河三趾马与贾氏三趾马为代表 ,牛科化石组合在种级甚至属级上有明显的区别。大量的陕西转角羚羊 ,小型的Protoryx、Dorcadoryx以及Ga
Since the 1960s, the Lantian region of Shaanxi Province has become one of the classic areas to study the contrast of late-Cenozoic mammals and strata in China with continuous Late Cenozoic strata and abundant mammalian fossils. Li Chuanbo et al. (1984) established the Qionghe Period from the mammalian fossils found in the Tahe Formation and compared it with the Vallesian period in Europe. Qiu Zhanxiang et al. (1990, 1995) considered the evidence of fossils inadequate and merged them with Baode Period. In recent years, a large number of chronological data of the trigeminal horse red clay in the Loess Plateau indicate that the earliest red clay deposition may begin before about 8Ma. Therefore, the narrow Baode period may only represent late Late Miocene, and the issue of the re-division of the Late Miocene mammalian stage has been put forward again. Since 1997, we have found a total of 52 fossil sites in the Lam Tin area. Of these, 26 have fossil mammals and a total of 1 666 large mammal fossil specimens. After detailed field stratigraphy surveys, a comprehensive stratigraphic profile was plotted and the locations of the major mammalian fossils were compared to the integrated stratigraphic profile. After preliminary research on various types of fossils and the preliminary revision of existing fossil materials, up to now, 45 species of mammalian fossils and 20 species of Lantian Group have been discovered in Tahe Formation of Lam-tian, Shaanxi Province. New fossil evidence indicates that the mammalian fossil assemblage found in the Tahe Formation is completely different from the typical Baodian three-toed horse fauna. Large mammal fossils to the river trigeminal horse and jasper three toe horses as representatives, bovine fossil assemblage in the genus or even genus have obvious differences. A large number of Shaanxi antelope, small Protoryx, Dorcadoryx and Ga