Ordovician strata

• 奥陶系

Ordovician strata的用法和样例：

例句

1. The Ordovician structure in the middle and east part of the Erdos Basin is a gently west-dipped large monocline.
   鄂尔多斯盆地的中东部奥陶系今构造为一平缓的西倾大单斜。
2. Finally the stratigraphic ages and correlation of the Ordovician lithostratigraphic units in the study area are discussed.
   笔者认为，申扎组应被废弃，德悟卡下组底界应作修订，并对该地区奥陶系岩石地层单位进行了简要的时代讨论和对比。