Detrital zircon geochronology of pre‐Tertiary strata in the Tibetan‐Himalayan orogen

Abstract

[1] Detrital zircon data have recently become available from many different portions of the Tibetan-Himalayan orogen. This study uses 13,441 new or existing U-Pb ages of zircon crystals from strata in the Lesser Himalayan, Greater Himalayan, and Tethyan sequences in the Himalaya, the Lhasa, Qiangtang, and Nan Shan-Qilian Shan-Altun Shan terranes in Tibet, and platformal strata of the Tarim craton to constrain changes in provenance through time. These constraints provide information about the paleogeographic and tectonic evolution of the Tibet-Himalaya region during Neoproterozoic to Mesozoic time. First-order conclusions are as follows: (1) Most ages from these crustal fragments are <1.4 Ga, which suggests formation in accretionary orogens involving little pre-mid-Proterozoic cratonal material; (2) all fragments south of the Jinsa suture evolved along the northern margin of India as part of a circum-Gondwana convergent margin system; (3) these Gondwana-margin assemblages were blanketed by glaciogenic sediment during Carboniferous-Permian time; (4) terranes north of the Jinsa suture formed along the southern margin of the Tarim-North China craton; (5) the northern (Tarim-North China) terranes and Gondwana-margin assemblages may have been juxtaposed during mid-Paleozoic time, followed by rifting that formed the Paleo-Tethys and Meso-Tethys ocean basins; (6) the abundance of Permian-Triassic arc-derived detritus in the Lhasa and Qiangtang terranes is interpreted to record their northward migration across the Paleo-and Meso-Tethys ocean basins; and (7) the arrival of India juxtaposed the Tethyan assemblage on its northern margin against the Lhasa terrane, and is the latest in a long history of collisional tectonism.

Silurian high-pressure granulites from Central Qiangtang, Tibet: Constraints on early Paleozoic collision along the northeastern margin of Gondwana

“…510-470 Ma) in the Himalaya Cawood and Buchan, 2007;Wang et al, 2012), Lhasa (Zhu et al, , 2013Hu et al, 2013), and South Qiangtang Hu et al, 2010;Zhu et al, 2013) terranes can best be interpreted as a product of the subduction of the Proto-Tethyan oceanic lithosphere beneath the northern margin of Indo-Australian Gondwana. As described by Gehrels et al (2011), it appears that two other convergent margin systems were present between the northern margin of IndoAustralian Gondwana and outboard micro-continental ribbons (e.g. Tarim-Northern China) during early Paleozoic time:…”

Garnet effect on Nd-Hf isotope decoupling: Evidence from the Jinfosi batholith, Northern Tibetan Plateau

“…The Mohe gneiss within the NQ-UHPM is the oldest sampled crystalline basement in the QOB, dated at ~ 2.5 Ga , and the inherited zircons with ages >2.6 Ga confirm the existence of an Archean basement in the region (Huang et al, 2015;. Different models have been proposed to explain the tectonic evolution in the whole QOB (Xu et al, 1994;Yin and Harrison, 2000;Yang et al, 2002;Gehrels et al, 2003Gehrels et al, , 2011Song et al, 2006Song et al, , 2013Song et al, , 2014Wu et al, 2006Wu et al, , 2010Xu Z. Q, 2006;Xiao et al, 2009;Huang et al, 2015). The…”

Constraints on the paleogeographic evolution of the North China Craton during the Late Triassic–Jurassic

“…It is difficult to trace the actual source of Precambrian zircons in the Phanerozoic sandstones (Gehrels et al, 2011) because the zircons might have experienced several episodes of recycle before they were accumulated in the Phanerozoic sediments. The studied Late Triassic-Jurassic samples all contain abundant Precambrian zircons (1.5-2.1 and 2.1-2.9 Ga) (Table S1; Figs.…”