Zircon U-Pb and Hf isotope constraints on the Mesozoic tectonics and crustal evolution of southern Tibet

Abstract

Research Article| September 01, 2006 Zircon U-Pb and Hf isotope constraints on the Mesozoic tectonics and crustal evolution of southern Tibet Mei-Fei Chu; Mei-Fei Chu 1Department of Geosciences, National Taiwan University, Taipei, Taiwan Search for other works by this author on: GSW Google Scholar Sun-Lin Chung; Sun-Lin Chung 1Department of Geosciences, National Taiwan University, Taipei, Taiwan Search for other works by this author on: GSW Google Scholar Biao Song; Biao Song 2Institute of Geology, Chinese Academy of Geological Sciences, Beijing, China Search for other works by this author on: GSW Google Scholar Dunyi Liu; Dunyi Liu 2Institute of Geology, Chinese Academy of Geological Sciences, Beijing, China Search for other works by this author on: GSW Google Scholar Suzanne Y. O'Reilly; Suzanne Y. O'Reilly 3Australian Research Council National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC), Department of Earth and Planetary Sciences, Macquarie University, Sydney, Australia Search for other works by this author on: GSW Google Scholar Norman J. Pearson; Norman J. Pearson 3Australian Research Council National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC), Department of Earth and Planetary Sciences, Macquarie University, Sydney, Australia Search for other works by this author on: GSW Google Scholar Jianqing Ji; Jianqing Ji 4School of Earth and Space Sciences, Peking University, Beijing, China Search for other works by this author on: GSW Google Scholar Da-Jen Wen Da-Jen Wen 5Department of Geosciences, National Taiwan University, Taipei, Taiwan Search for other works by this author on: GSW Google Scholar Author and Article Information Mei-Fei Chu 1Department of Geosciences, National Taiwan University, Taipei, Taiwan Sun-Lin Chung 1Department of Geosciences, National Taiwan University, Taipei, Taiwan Biao Song 2Institute of Geology, Chinese Academy of Geological Sciences, Beijing, China Dunyi Liu 2Institute of Geology, Chinese Academy of Geological Sciences, Beijing, China Suzanne Y. O'Reilly 3Australian Research Council National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC), Department of Earth and Planetary Sciences, Macquarie University, Sydney, Australia Norman J. Pearson 3Australian Research Council National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC), Department of Earth and Planetary Sciences, Macquarie University, Sydney, Australia Jianqing Ji 4School of Earth and Space Sciences, Peking University, Beijing, China Da-Jen Wen 5Department of Geosciences, National Taiwan University, Taipei, Taiwan Publisher: Geological Society of America Received: 20 Feb 2006 Revision Received: 11 Apr 2006 Accepted: 14 Apr 2006 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2006) 34 (9): 745–748. https://doi.org/10.1130/G22725.1 Article history Received: 20 Feb 2006 Revision Received: 11 Apr 2006 Accepted: 14 Apr 2006 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Mei-Fei Chu, Sun-Lin Chung, Biao Song, Dunyi Liu, Suzanne Y. O'Reilly, Norman J. Pearson, Jianqing Ji, Da-Jen Wen; Zircon U-Pb and Hf isotope constraints on the Mesozoic tectonics and crustal evolution of southern Tibet. Geology 2006;; 34 (9): 745–748. doi: https://doi.org/10.1130/G22725.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The first in situ Hf and U-Pb isotope analyses of zircon separates from Mesozoic granites in southern Tibet identify a significant, previously unknown stage of magmatism. Igneous zircons (n = 34) from a granite within the Gangdese batholith show a weighted mean 206Pb/238U age of 188.1 ± 1.4 Ma and εHf(T) (the parts in 104 deviation of initial Hf isotope ratios between the zircon sample and the chondritic reservoir) values between +10.4 and +16.8, suggesting predominantly Early Jurassic intrusive activity with a juvenile mantle contribution. Of 40 inherited zircons from two Cretaceous S-type granites in the northern magmatic belt, 23 delineate a slightly older 206Pb/238U age cluster between 188 and 210 Ma. These zircons have εHf(T) values from −3.9 to −13.7, yielding crustal Hf model ages from ca. 1.4 to 2.1 Ga, suggesting a major episode of crustal growth in Proterozoic time and remelting of this crust in Early Jurassic time. Combining these with literature data, we interpret the Jurassic Gangdese magmatism as an early product of the Neo-Tethyan subduction that played a long-lasting role in the tectonic evolution of southern Tibet prior to the India-Asia collision. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.