摘要
根据江苏泰县N 4井五通组观山段顶部的胞石Grahnichitinapilosa的发现 ,确定观山段的时代为中泥盆世吉维特期。据此认为 :擂鼓台段的两层暗色泥岩 ,应分别对比为南洞页岩、长顺页岩 ;中泥盆世大海侵时 ,华南海沿苏皖河经皖南、苏南入侵苏北。
There have been three opinions concernig the age of the lower division, the Guanshan Member of the Wutung Formation since the paper by Ting (1919), who then called it the Wutungshan Quatzite, namely 1) Givetian to early Frasnian (Feng, 1987), 2) Frasnian (Li, 1963, 1965; Cai and Li, 1982; Li et al. , 1984), and 3) Strunian (Cai et al. , 1998). However, no reliable age indicators were found within the member. At a depth of 2 358 m of Well N 4 in Taixian of N. Jiangsu gray argillaceous siltstone sandwiched within redbeds yields the chitinozoan species Grahnichitina pilosa (Collinson et Scott, 1958). This species was ever widespread in the world, including U.S.A. (Collinson and Scott, 1958, Dunn, 1959, Morgan,1967, Urban ,1972), Brazil (Boekel, 1968), Ghana (Anan Yorke 1974), Libya (Paris et al. , 1985, Streel et al., 1988), Argentina (Volkheimer et al. , 1988), Algeria (Boumendjel, 1987), and China. It was recorded from the Solon and Lower Rapid members of the Cadar Valley Formation of Illinois and Iowa (Collinson and Scott, 1958, Dunn, 1959, Urban, 1972) where the conodonts are representative of the Middle varcus to hermanni cristatus zones of Givetian age. Therefore, the discovery of G. pilosa confirms a Givetian age for the subsurface Guanshan Member.
出处
《古生物学报》
CAS
CSCD
北大核心
2000年第4期535-543,共9页
Acta Palaeontologica Sinica
基金
中国科学院南京地质古生物研究所现代古生物学和地层学开放实验室基金
中国科学院古生物与古人类学特别支持费资助项目
关键词
胞石
观山段
五通组
中泥盆地
Grahnichitina pilosa , chitinozoans, Guanshan Member, Wutung Fm., Middle Givetian, Jiangsu
