内蒙古新巴尔虎左旗罕达盖地区早泥盆世化石的发现及其意义

THE DISCOVERY OF EARLY DEVONIAN FOSSILS IN THE HANDAGAI AREA OF XINBAERHU LEFT COUNTY OF INNER MONGOLIA AND ITS SIGNIFICANCE

2007年在内蒙古自治区呼伦贝尔市新巴尔虎左旗罕达盖地区开展1/5万矿产调查时,在原划分为中奥陶统多宝山组的灰岩中首次发现早泥盆世化石:牙形刺Pseudooneotodus beckmanni,Belodella resima,Belodella devonica,?Caudicriodus sp.;竹节石Nowakia sp.,?Homoctenus sp.;介形虫Tricornina sp.,Praepilatina sp.,Tetrasaculus sp.,Microcheilinella sp.,从而将这套缺少时代依据的地层确定为早泥盆世,归为泥鳅河组。

During mapping in the Handagai area of Xinbaerhu Left County, Inner mongolia in 2007, We discovered Early Devonian fossils in the limestone of the Duobaoshan Formation that was formerly mapped as a Middle Ordovician stratigraphic unit. These fossils include the conodonts Pseudooneotodus beckmanni, Belodella resima ,Belodella devonica , ？ Caudicriodus sp. , the tentaculites Nowakia sp. , ？ Homoctenus sp. , Ostracoda Tricornina sp. , Praepilatina sp. , Tetrasaculus sp. , Microcheilinella sp.. These fossils suggest an Early Devonian age and the fossiliferous limestone is mapped as the Niqiuhe Formation.