n.筆石綱

These provide base for the correct measurement and valuing of graptolite reflectivity. 從而為筆石反射率的正確測定和取值奠定了基礎(chǔ)。

The Ordovician graptolite bearing beds have been found from the core of Tadong 2 borehole in the northeastern Tarim Basin, Xinjiang. 塔里木盆地東部塔東2井巖心中新發(fā)現(xiàn)了一些奧陶系筆石化石,這些筆石標(biāo)本呈炭質(zhì)薄膜狀,保存在該井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. 在平面圖中,22個(gè)點(diǎn)可劃分為2個(gè)點(diǎn)群,分別代表中國早奧陶世的兩大筆石動(dòng)物群,即華南型筆石動(dòng)物群和華中型筆石動(dòng)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. 該組中采獲了低等蕨類植物、牙形石和筆石等化石，證實(shí)其時(shí)代屬于早泥盆世-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. 下志留統(tǒng)龍馬溪組厚10m