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就华南板块而言,志留纪晚期(Ludlow世—Pridoli世)近岸浅海、非笔石相地层多分布在边缘海湾处,是否在扬子地台内部发育,以往尚无确凿记载。依据来自湘西北张家界—桑植地区新近发现的微体化石(主要指植物碎片),确认志留纪晚期地层在扬子地台内部确实存在。对原小溪组(又称小溪峪组)进行厘定,将它“一分为二”:上部仍称小溪组,命名地在桑植瑞塔铺,发育最好的是张家界温塘剖面,岩性为黄绿色碎屑岩,富含大型虫管遗迹化石,时代为Ludlow晚期—Pridoli早期;下部称迴星哨组,归于Llandovery统Telychian阶上部。小溪组与迴星哨组之间为假整合接触,缺失Telychian末期、Wenlock世和Ludlow世早期地层。由此得出结论:在“扬子上升”后,扬子地台内部曾被志留纪晚期的海水侵漫;对其他地区迴星哨组与上覆地层的研究需要细化。
In the case of the South China Plateau, there is no definite record in the past whether the Silurian (Ludlow-Palaidic) nearshore shallow sea and non-penolithic strata are distributed at the edge of the Gulf. Based on newly discovered microfossils (mainly plant fragments) from Zhangjiajie-Sangzhi area in northwestern Hunan, it was confirmed that the Late Silurian strata actually existed inside the Yangtze platform. The original stream group (also known as Xiaoyu group) to be determined, it One is divided into two : the upper is still said that the stream group, named in the Sangzhi Ruita shop, the best development is Zhangjiajie temperature Tong section, the lithology of yellow-green clastic rocks, rich in large-scale insect tube fossils, the era of Late Ludlow -Pridoli early; the lower back to the Star whistle group, attributed to Llandovery Unified Telychian upper part. There was a false integration between the stream group and the return star group, missing the early strata of Telychian, Wenlock and Ludlow. From this, we can conclude that the interior of the Yangtze platform had been invaded by the seawater late in the Silurian after the rise of Yangtze, and the study of the Hui-hun formations and overlying formations in other areas needed to be refined.