Wednesday, 29 August 2007 - 12:10 PM
Review of detrital zircon age and Sm-Nd isotopic data from Himalaya -Support to the Precambrian formation of East Antarctica
Masaru Yoshida, Gondwana Institute for Geology and Environment, 147-2 Hashiramoto, Hashimoto, Japan and Bishal Nath Upreti, Department of Geology, Trichandra Campus, Tribhuvan University, Ghata Ghar, Kathmandu, Nepal.
Published detrital zircon ages and Sm-Nd isotopic data from Himalayan Orogen suggest that the Lesser Himalayan Metasediments (LHM) might have received material from the Northern Indian Craton, while the Higher Himalayan Gneisses (HHG) mostly from the Circum-East Antarctic Orogen including Western Australia and East Antarctica, and partly from the LHM and the Arabian Nubian Shield (Yoshida and Upreti, 2006, Gondwana Research 10, 349). The original material of the Tibetan Tethys Sedimentary Sequence is considered to be mostly derived from the HHG and partly from the CEAO and only small amount on the western area from the Arabian Nubian Shield. The above results do not support the isolated block of the Indian craton during the Neoproterozoic apart from other crustal blocks, but suggest the juxtaposition of the Indian Craton with the Mesoproterozoic CEAO during the Neoproterozoic, and thus Mesoproterozoic or earlier formation of the East Gondwana as well as East Antarctica.