Integrated Biogeographical, Sedimentological, and Geochemical Constraints on the Late Cambrian Paleogeography of the North China (Sino-Korean) Block: Implications on Reconstructing the Eastern Gondwanan Margin

Interpretation of the early Paleozoic geographic location of the North China block has been problematical. While the associations of Australia, India, and Antarctica as the core components of the eastern Gondwanan margin are widely accepted, the location of major outboard blocks such as South China and North China is highly contested. A review of late Cambrian (Furongian) trilobite biogeography shows strong correlation of faunal assemblages between North and South China, and between North China and the eastern Himalayan margin in Bhutan. Sedimentological evidence for a tectonic event around the Cambrian-Ordovician boundary exists in both North China and South Korea, which parallels a Cambro-Ordovician tectonic event seen in the Himalayan margin. Furthermore, some, but not all, detrital zircon spectra from Cambrian strata in North China are similar to that of spectra from the Cambrian Himalaya, and to other parts of core Gondwanaland, suggesting the North China shelf was receiving a similar array of materials to deposits forming contemporaneously in the Himalaya. In combination, these data argue for placement of the North China Block 1) in close association to core Gondwanaland and 2) in closer proximity to the north Indian margin in the late Cambrian than is generally presented. These conclusions are also consistent with the faunal similarity between South and North China, and the close similarities in earlier Cambrian and late Neoproterozoic biota and stratigraphic architecture of South China and the Himalayan margin.