Multiple mineralization events in the eastern Tianshan district, NW China: Isotopic geochronology and geological significance

New 40Ar/39Ar age constraints on the Late Palaeozoic tectonic evolution of the western Tianshan (Xinjiang, northwestern China), with emphasis on Permian fluid ingress

“…Gold mineralisation peaked in the Early Permian, that is 290-270 Ma, related to regional-scale, convective fluid circulation associated to granite intrusions and controlled by transcrustal strike-slip shear zones (Rui et al 2002;Han and Zhao 2003;Zhang et al 2003;Mao et al 2004bMao et al , 2005Zhang et al 2008a). Part of the mineralisation occurred in the Palaeozoic sedimentary series of the Central Tianshan domain, including in partly volcanic series of Late Carboniferous to Late Permian age Yang et al 2006;Liu et al 2007).…”

“…However, mineralisations continued into the Late Triassic (Zhang et al 2008a), including shear zone hosted gold deposits with 40 Ar/ 39 Ar ages of 220.6 ± 0.6 to 222.5 ± 1.2 Ma (Zhu et al 2006), and of 208.3 ± 0.6 to 210.6 ± 1.0 Ma (Liu et al 2007). At Muruntau in Uzbekistan mineralisation similarly continued into the Triassic, at least 30 Ma later than subjacent felsic intrusions, as indicated by 245 and 220 Ma 40 Ar/ 39 Ar ages of hydrothermal sericite from selvages to auriferous quartz veins (Wilde et al 2001).…”

“…Dobretsov 2003;Zhou et al 2004;Kovalenko et al 2004;Berzina and Sotnikov 2007;Tsygankov et al 2007;Pirajno et al 2008;Zhang et al 2008a). However, in recent years the view that deep mantle plumes are responsible for the formation of large volcanic provincessuch as the classic examples of Hawaii and Pacific seamount trails, Iceland and Yellowstone-has been challenged by amongst others: Humphreys et al (2000), Christiansen (2001), Christiansen et al (2002), Foulger (2002, Foulger and Natland (2003) and Koppers and Staudigel (2005).…”

“…Similarly, part of the Late Palaeozoic mineralisations occurred closely related to such transcrustal shear zones in which permeability is structurally enhanced, thus providing principal pathways for regional fluid flow (Yakubchuk et al 2002;Mao et al 2004bMao et al , 2005. The Tianshan in China and the adjacent central Asian republics of the former Soviet Union hosts some of the world's largest gold deposits (Konopelko et al 2007;Rui et al 2002;Yakubchuk et al 2002;Mao et al 2004bMao et al , 2005Zhang et al 2008a). Auriferous quartz veins are tracers of high-flux aqueous flow in the crust (Sibson 2007).…”

Petrogenesis of gold-mineralized magmatic rocks of the Taerbieke area, northwestern Tianshan (western China): Constraints from geochronology, geochemistry and Sr–Nd–Pb–Hf isotopic compositions

“…Porphyry Cu-Au-Mo, epithermal and orogenic gold deposits are widely distributed in the belt, and are world-class (Yakubchuk, 2004;Seltmann and Porter, 2005), and most of the deposits were generated during the Late Paleozoic (Seltmann and Porter, 2005). However, for a long time, tectonic (arc, rift or post-collisional) settings and the geodynamic processes associated with these Late Paleozoic metal deposits have been disputed (e.g., Rui et al, 2002;Xiao et al, 2003Xiao et al, , 2004aXiao et al, , 2009Xiao et al, , 2012Jahn, 2004;Xia et al, 2004Xia et al, , 2008Xia et al, , 2012Zhou et al, 2004;Mao et al, 2008;Pirajno et al, 2008;Zhang et al, 2008;Yang and Zhou, 2009;Han et al, 2010;Qin et al, 2011).…”