Rescue of Late Eocene Vertebrates; Yuanqu Basin, China

元曲盆地是一个面积约350平方公里的山间构造。位于中国中部中条山脉内。该盆地的始新世至渐新世陆相岩石是亚洲这个时代脊椎动物化石的最佳记录之一，迄今为止，包括至少50种哺乳动物和5种爬行动物。这些化石矿床是由一位瑞典地质学家于1916年发现的，他的收藏构成了一本关于中国早期第三纪脊椎动物的专著的核心。自从这次早期的探险以来，古生物学家们参观了这个盆地，并收集了河堤组的脊椎动物化石。结果，至少有20个分类群被添加到原始名单中，其中许多是关于哺乳动物的宝贵资料。1993年，中华人民共和国将在黄河上修建一座大坝，至少15个重要的化石遗址将被淹没。本项目是中美两国古生物学家的合作项目，旨在从这些遗址中提取化石，并对淹没前的古地磁特征进行表征。这个项目的意义在于，它提供了最后的机会，从河南河堤组中抢救出宝贵的古生物材料中国。本区地层已知，始新世下半叶有丰富的脊椎动物记录。在该地区发生洪水之前，中美联合考察队将从即将消失的遗址中打捞出含有化石的材料。这是非常重要的，因为这个特殊的地层在沉积物中保存了形态完整的标本，因此，这些化石将揭示一个动态间隔，当气候，始新世-渐新世事件发生了动物和生物地理变化。

The Yuanaqu Basin is an intermontane structure covering about 350 sq. km within the Zhongtiao Range of central China. Eocene to Oligocene terrestrial rocks in this basin contain one of the best records for vertebrate fossils of this age in Asia, including, to date, at least 50 species of mammals and five of reptiles. These fossiliferous deposits were discovered in 1916 by a Swedish geologist whose collections formed the core of a monograph on early Tertiary vertebrates of China. Since this early expedition paleontologists have visited this basin and collected fossil vertebrates in the Heti Formation. As a result, at least 20 taxa have been added to the original list and many represent valuable material on mammals. In 1993 the People's Republic of China will build a dam on the Huanghe (Yellow) River, and at least 15 important fossil-bearing sites will be submerged. This project is a collaborative effort between Chinese and American paleontologists to retrieve fossils from these sites and characterize the paleomagnetics prior to submersion. %%% The significance of this project is that it offers the last opportunity to salvage valuable paleontological material from the Heti Formation in China. The stratigraphy of this region is well known and it has a rich record of vertebrates in the latter part of the Eocene. Prior to flooding of this region, the combined Chinese and American teams will salvage fossil bearing materials from the sites that will be lost. This is very important because this particular formation has morphologically complete specimens preserved in deposits, and as such, these fossils will shed light on a dynamic interval, when the climatic, faunal, and biogeographic changes of the Eocene-Oligocene event occurred.