Trilobite-constrained Ordovician biogeography of China with reference to the faunal connections with Australia
Contents
Abstract
All the plates and most of the terranes in China exhibit close biogeographic links and may have formed part of eastern Peri-Gondwana during the Ordovician. Synthetic analysis based largely on the platform/inner shelf trilobite faunas suggests that the Chinese eastern Peri-Gondwanan plates and terranes may have belonged to a single biogeographic province during the Tremadocian (Tremadoc) and late Katian-Hirnantian (Ashgill), but may be separated into two sub-provinces during the Floian-early Katian (Arenig-Caradoc): one consists of South China, Tarim and Annamia, and the other may include North China, Sibumasu, Southern Tibet, Tianshan-Beishan and possibly Hainan. However, the deep-water facies trilobites of the relevant Chinese geographic units had progressively become more unified from the mid Darriwilian to early Katian (Llanvirn to Caradoc) before the sub-provinces eventually broke down by the late Katian (Ashgill). Australian Ordovician trilobite faunas had close affinities with most of the Chinese eastern Peri-Gondwanan plates and terranes, but closest biogeographic links were in particular with North China and Middle Tianshan-Beishan.