吉林磐石七间房剖面石炭系鹿圈屯组的牙形刺及时代

摘要

在吉林磐石七间房剖面上部的两个样品(Lqt 22和Lqt 26)中发现了牙形刺Declino gnathodus bernesge,D.inaequalis、D.noduliferous s.l.及D.praenoduliferous.这一动物群的时代清楚地表明七间房剖面鹿圈屯组上部的时代为晚石炭亚纪巴什基尔期(Bashkirian)的早期,可精确确定为D.praenoduliferous带晚期至D.noduliferous带早期.吉中地区石炭系的中间界线无疑在鹿圈屯组内部.%Conodonts are found in two samples collected from the upper part of Qijianfang section in Panshi of central Jilin Province, including Declinognathodus bernesge, D. inaequalis, D. noduliferous sensu lato and D. praenoduliferous. This fauna clearly indicated that the the sampled strata were the early Bashkirian of Late Carboniferous, precisely from the upper D. praenoduliferous zone to lower D. noduliferous zone. The intermediate line of Carboniferous was determined in the interval of the Lujuantun Formation in Jilin.