Early Jurassic decratonic gold metallogenesis in the eastern North China Craton: Constraints from S-Pb-C-D-O isotopic systematics and pyrite Rb-Sr geochronology of the Guilaizhuang Te-Au deposit

Abstract

The North China Craton (NCC) is a window to decratonization and associated gold metallogenesis during the Mesozoic. Although Early Cretaceous gold mineralization associated with craton destruction has been reported, information on decratonic gold metallogenesis during the other periods remain scarce. Here we investigate the Guilaizhuang crypto-explosive breccia-type Te-Au deposit from eastern NCC and present Rb-Sr geochronological data on pyrite which provide new constraints on the timing of mineralization as 180.8 ± 2.3 Ma, corresponding to Jurassic gold metallogenesis. The S-Pb-C-O isotopic systematics and the (87Sr/86Sr)i value of the pyrite as ca. 0.712429 ± 0.000076 suggest that the ore-forming nutrients were derived from crustal and mantle sources. The Guilaizhuang Te-Au deposit formed during the tectonic transformation from compression to extension associated with the extensional collapse of the Dabie–Sulu UHP orogen and the delamination of the NCC lithosphere, triggering mantle upwelling and extensive crustal melting.