资源环境科技发展态势分析平台

The Central Asian Orogenic Belt is complex and little understood in its geotectonic history. Here we apply a new approach to conclude on the paleogeography of major Mongolian terrains using small skeletal fossil assemblages and a combined analysis of U-Pb ages and typology of detrital zircons. We document a new Cambrian Stage 3 fauna from the Telmen Block located between the Dzhabkan and Tuva-Mongolia cratons. Based on a hierarchical cluster analysis of 35 blocks, we observe the most robust biogeographic relationship between Telmen and Kusnetzk Alatau and between Tuva- Mongolia and Lake Zone. These results challenge the view that these cratons were assembled during the Ediacaran/Cambrian in a single ribbon-shaped paleocontinent. Detrital zircon U-Pb ages indicate a unique age population at ∼516 Ma at Telmen derived from I-type granitoids, neither seen on Dzhabkan nor Tuva-Mongolia cratons supporting their different tectonic evolution within the Palasian Ocean after the breakup of Rodinia.