The Cambrian and Ordovician Systems in the South Side of Eurasia and the Origin of the Tethys Sea

Abstract

The trans-Eurasiatic faunal connection in the early Phanerozoic eon ia an important problem in geology, as it concerns the origin of the Tethyan sea. When I proposed the Tsinling-Keijo (i.e. Seoul) line in 1930, I traced the southern fauna from South Korea to Northern Europe through Pamir and Kirghiz Steppe, because none was known of the Eo-Palaeozoic fossis in Near and Middle East. Two years later however, I could confirm the route of migration from South France to Eastern Asia with the distribution of the Dikelokephaliniidae.
In 1976 I classified the early Cambrian biogeography into the Redlichian, Olenellidian and intermediate provinces in the last of which extending from Morocco to Northern Siberia, the olenellids and redlichids coexisted. In the present knowledge the Redlichian province reaches as far as Sardinia in the Mediterranean sea. In the Middle Cambrian period on the contrary the Paradoxidian province expanded into Turkey, while the Tokinella-Oryctocephalus fauna is traceable to Kashimir, although Iran is still a question. Recently it was ascertained by the discovery of Maladioidella that the oriental trilobites have migrated westerly to the Iberian peninsula in the late Cambrian period. Of the early and middle Ordovician ages the Asaphopsis-Taihungshania-Neseuretus fauna distributed through the Tethyan sea, although the late Ordovician faunal aspect is not so well clarified in the area.