甘肃省北祁连山地区典型的石炭系—二叠系海陆过渡相沉积中牙形刺较为丰富。对该区三个剖面进行牙形刺的系统研究,鉴定牙形刺9属27种。识别出11个牙形刺带或组合带,从下至上依次为Gnathodus bilineatus bilineatus,G.bilineatus bollandensis,Idiognathoides sulcatus sulcatus,Id.sinuatus,Idiognathodus delicatusI.magnificus,I.podolskensis,Swadelina subexcelsus,Sw.makhlinae,Streptognathodus oppletus-S.elegantulus,S.elongatus和S.barskovi带或组合带。该牙形刺序列可与我国其他地区进行对比,为北祁连山地区提供了高精度的牙形刺生物地层格架。牙形刺的丰度受沉积相控制。
The North Qilian Mountain region bears typical Carboniferous-Permian (C-P) marine-continental transitional deposits that is marked by relatively abundant conodonts. In this paper, conodonts from C-P strata in three sections in this area were investigated systematically. In total, 27 species assigned to 9 genera were recorded. Eleven conodont zones or assemblage zones have been recognized. They are Gnathodus bilineatus bilineatus, G. bilineatus bollandensis, Idiognathoides sulcatus sulcatus, Id. sinuatus, Idiognathodus delicatus-I, magnificus, I. podolskensis , Swadelina subexcelsus , Sw. makhlinae , Streptognathodus oppletus-S, elegantulus, S. elongatus and S. barskovi zone or assemblage zone in ascending order. This conodont succession can be successfully correlated with the counterparts reported from other areas in China and this provides a high-resolution biostratigraphical framework for the North Qilian Mountain region. The abundance of conodonts might be controlled by certain factors like the sedimentary facies.