五峰阶（Wufengian Stage）位于石口阶之上，曾用于中国上奥陶统顶部的一个阶，大致与欧洲的阿什极尔阶相当。五峰阶自下而上含有六个笔石带：①Pleurograptus lui带；②Dicellograptus szechuanensis带；③Tangyagraptus typicus带；④Diceratograptus mirus带；⑤Paraorthograptus typicus带和⑥Diplograptus bohemicus带。后人厘定为五个化石带，自下而上为：①Dicellograptus complexus带，②Tangyagraptus typicus带，③Paraort...
五峰阶（Wufengian Stage）位于石口阶之上，曾用于中国上奥陶统顶部的一个阶，大致与欧洲的阿什极尔阶相当。五峰阶自下而上含有六个笔石带：①Pleurograptus lui带；②Dicellograptus szechuanensis带；③Tangyagraptus typicus带；④Diceratograptus mirus带；⑤Paraorthograptus typicus带和⑥Diplograptus bohemicus带。后人厘定为五个化石带，自下而上为：①Dicellograptus complexus带，②Tangyagraptus typicus带，③Paraort...