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The Silurian palaeontology and stratigraphy of the Qinghai-Tibetan Plateau have been studied for more than 100 years. With the launch of the Second Tibetan Plateau Scientific Expedition and Research, it is necessary to update the summaries of the Silurian stratigraphy and fossil assemblages of the Qinghai-Tibetan Plateau and their correlation with its surrounding areas. In this study, we have selected 33 sections from the Qinghai-Tibetan Plateau and its surroundings areas, summarised the available data in terms of stratigraphic regionalisation, lithostratigraphy, chronostratigraphy, and biostratigraphy, and divided the study area into four stratigraphic provinces: the Xizang-Western Yunnan-Western Sichuan Province, the Kunlun-Qilian Province, the South China Province, and the Tarim Province. In general, the Silurian strata in the Qinghai-Tibetan Plateau is more complete than those in other areas of China. Palaeobiogeographical studies of the vertebrate faunas, sporomorph assemblages, and brachiopod faunas of the study area indicate a closer geographical relationship between the South China, Tarim, and Indochina palaeoplates, than previously considered. Compared with the surrounding areas where Silurian strata have been extensively studied, the study of Silurian strata in the main part of the Qinghai-Tibetan Plateau is still in the preliminary stage. In the future, it is necessary to conduct research on the age, distribution, and resource potential of basal Silurian black shales to provide new directions for shale gas exploration and development in China. The shallow marine strata of the middle to upper Silurian require further subdivision. Considering that the Silurian System in the Qinghai-Tibetan Plateau is more complete, it has the potential to supplement and improve the study of the carbon isotope stratigraphy of the Silurian in China.

AbstractA detailed Furongian to Tremadocian conodont biostratigraphy is established from the Saluk Mountains located in southern Kopet-Dagh, northeast Iran. Thirty species assigned to 17 genera were recovered from decimetre-scale limestone beds in a fine-grained siliciclastic succession, deposited in an intraplate rift system. The following biozones are established for the region, in ascending order: Proconodontus muelleri, Eoconodontus, Cordylodus intermedius, Cordylodus lindstromi, Cordylodus angulatus, Paltodus deltiferand Acodus triangularisinterval zone. This low-to medium-richness conodont fauna comprises cosmopolitan euconodont species of Proconodontus, Eoconodontus, Cordylodus, Teridontus nakamurai, Semiacontiodus nogamiiand a few long- ranging proto- and paraconodont species, which inhabited a narrow marine basin flanked by landmasses and formed by active rifting. It lacks shallow water tropical taxa and probably belongs to the Cold Domain of the Shallow Sea Realm. The occurrence of conodonts of the Paltodus deltiferBiozone in the uppermost part of the Qyzlar Formation in the Ghelli section suggests that the major episode of flood basalt volcanism in south Kopet-Dagh commenced in the late Tremadocian.Hadi Jahangir [Jahangir.hadi@nigpas.ac.cn] and Guanzhou Yan [gzyan@nigpas.ac.cn], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, PR China.