Detrital-zircon geochronology of the northeastern Tibetan plateau

Research Article| July 01, 2003 Detrital-zircon geochronology of the northeastern Tibetan plateau George E. Gehrels; George E. Gehrels 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar An Yin; An Yin 2Department of Earth and Space Sciences, University of California, Los Angeles, California 90095-1567, USA Search for other works by this author on: GSW Google Scholar Xiao-Feng Wang Xiao-Feng Wang 3Chinese Academy of Geological Sciences, Institute of Geomechanics, Beijing, 100081, China Search for other works by this author on: GSW Google Scholar Author and Article Information George E. Gehrels 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA An Yin 2Department of Earth and Space Sciences, University of California, Los Angeles, California 90095-1567, USA Xiao-Feng Wang 3Chinese Academy of Geological Sciences, Institute of Geomechanics, Beijing, 100081, China Publisher: Geological Society of America Received: 15 Mar 2002 Revision Received: 22 Dec 2002 Accepted: 19 Jan 2003 First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2003) 115 (7): 881–896. https://doi.org/10.1130/0016-7606(2003)1152.0.CO;2 Article history Received: 15 Mar 2002 Revision Received: 22 Dec 2002 Accepted: 19 Jan 2003 First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation George E. Gehrels, An Yin, Xiao-Feng Wang; Detrital-zircon geochronology of the northeastern Tibetan plateau. GSA Bulletin 2003;; 115 (7): 881–896. doi: https://doi.org/10.1130/0016-7606(2003)1152.0.CO;2 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 SocietyGSA Bulletin Search Advanced Search Abstract U-Pb geochronologic analyses have been conducted on 413 detrital-zircon grains collected from 16 samples in the Altun Shan, Nan Shan, and Qilian Shan. The samples come primarily from quartz arenites and metaturbidites of Middle to Late Proterozoic age and from feldspathic and volcanic clast-rich sandstones of early Paleozoic age. Zircon grains in Proterozoic strata resting on Tarim basement yielded mainly 2.0–1.9 Ga ages, whereas Proterozoic strata of the Qaidam and Qilian terranes yielded mainly ca. 930–820 Ma and ca. 1.9–1.1 Ga ages. The younger grains were apparently shed from local igneous rocks, whereas the grains older than 1.1 Ga were shed from an undetermined continental source. Grains in the lower Paleozoic strata are mainly ca. 500–430 Ma and were shed from nearby plutonic and possibly volcanic rocks that formed in a magmatic arc setting.Our detrital-zircon ages are consistent with a model (first proposed by E.R. Sobel and N. Arnaud) in which early Paleozoic magmatism occurred within a single northeast-facing magmatic arc that was constructed across an assemblage of Middle to Late Proterozoic accretionary complexes, remnants of magmatic arcs, and shallow-marine strata. This arc system was accreted to the Tarim and Sino-Korean cratons during Silurian–Devonian time. The resulting suture has been reactivated as Tertiary thrust faults that currently define the structural and topographic margin of the Tibetan plateau.Our data also provide two new estimates for the offset along the eastern Altyn Tagh fault. A belt of Middle Proterozoic shallow-marine strata is offset by ∼400 km, whereas a belt of 490–480 Ma magmatic arc rocks is offset by ∼370 km. These values are generally similar to the 350–400 km offset reported in most previous studies. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.