n.笔石纲
These provide base for the correct measurement and valuing of graptolite reflectivity. 从而为笔石反射率的正确测定和取值奠定了基础。
The Ordovician graptolite bearing beds have been found from the core of Tadong 2 borehole in the northeastern Tarim Basin, Xinjiang. 塔里木盆地东部塔东2井岩心中新发现了一些奥陶系笔石化石,这些笔石标本呈炭质薄膜状,保存在该井4550。
These 22 points are divided into two groups, which,represent respectiyely, two graptolite types in the early ordovician, namely, the South China type and the Central China type. 在平面图中,22个点可划分为2个点群,分别代表中国早奥陶世的两大笔石动物群,即华南型笔石动物群和华中型笔石动物群。
We suggest that the strata are turbidite sequences that are deposisted on the passive continental margin.The strata containing plant, conodont and graptolite belongs to Early-Late Devonian. 该组中采获了低等蕨类植物、牙形石和笔石等化石，证实其时代属于早泥盆世-晚泥盆世。
The Longmaxi formation of Lower Silurian is ten metres in thickness,containing three graptolite zones:Glyptograptus persculptus,Parakidograptus acuminatus and Orthograptus vosiculosus. 下志留统龙马溪组厚10m
