辽宁西部第四纪哺乳动物及其地层时代

Quaternary mammals in western Liaoning and the age of the fossil-bearing strata

以大、小凌河流域为中心的辽西地区第四纪地层分布广泛,奥陶纪石灰岩为主的基岩使该地区喀斯特地貌发育,并在水溶蚀作用下形成洞穴,为哺乳动物栖息提供了理想的场所。20世纪70年代以前曾发现过建平、凌源西八间房、喀左鸽子洞和锦县沈家台等化石产地,之后陆续发现了喀左帽儿山洞穴、二布尺洞穴、朝阳马山洞和凌源沟门洞化石产地等。根据动物化石组合及其对比,辽西发现的这些化石群分别代表中更新世晚期、晚更新世早期、晚更新世中期和晚更新世晚期4个地质时代。这些材料的发现,对辽西乃至整个东北地区第四纪哺乳动物研究及区域第四纪地层的划分对比等具有重要意义。

The Quaternary deposits are widely distributed in western Liaoning, centered by Dalinghe River and XiaolingheRiver, where the Karst is very developed in the region geographically, mainly due to the Ordovician limestone as the bedrocks. Under the water solution, these carbonate rocks formed a lot of caves various in size, which provided ideal habitats for the mammals living during the Quaternary time. By 1970s, many sites yielding the mammal fossils were discovered in the region, such as Jianping, west Bajianfang of Lingyuan, Gezidong of Kazuo, Shenjiatai of Jinzhou. Since then, many new sites, e. g. Moershan of Kazuo, the Cave of Erchibu, Mashandong of Chaoyang, Goumendong of Lingyuan, were found one after another. According mainly to the fossil mammal assemblages and their comparisons, the fossils found from western Liaoning represent four geological stages： the late Middle Pleistocene, early Late Pleistocene, middle Late Pleistocene and late Late Pleistocene. These discoveries are very significant for the study of Quaternary mammals, and the divisions and correlation of Quaternary in western Liaoning even for whole Northeast China.