Resolving the Paleogeographic Puzzle of the Lhasa Terrane in Southern Tibet

The widespread Tibetan Permo-Carboniferous glaciogenic diamictites (PCGDs) are conventionally thought to be sourced from Indian Gondwana during glacier transport and deglaciation. However, the Lhasa PCGDs differ in detrital zircon U-Pb age spectra and epsilon(Hf)(t) values from those in Southern Qiangtang and Tethyan Himalaya. The similarities in epsilon(Hf)(t) values for similar-age detrital zircons, the development of glacier transport pathways, and the large volumes of the Tibetan PCGDs indicate an Australian source for the Lhasa PCDGs, and an Indian source for the Southern Qiangtang and Tethyan Himalayan PCDGs. We conclude that the Southern Qiangtang and Tethyan Himalayan are paleographically linked to northern India, whereas Lhasa is positioned adjacent to NW Australia during the Paleozoic. Magmatic and metamorphic records further indicate that eastern Lhasa (E90 degrees-E95 degrees) represents the outboard extension of events recorded in northern Central Australia, whereas western Lhasa (E80 degrees-E90 degrees) was located outboard of the West Australian Craton.

Automated summary

By analyzing the detrital zircon U-Pb age spectra and epsilon(Hf)(t) values of the glaciogenic diamictites (PCGDs) in different regions, it is found that the PCGDs in Lhasa have a different source from those in Southern Qiangtang and Tethyan Himalaya. The research suggests that the Lhasa PCGDs may have originated from Australia, while the PCGDs in Southern Qiangtang and Tethyan Himalaya may have come from India.