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The Junggar orogen, Xinjiang, China, is an important part of the Ural–Mongolian orogen. The collisional orogenesis in this region occurred primarily in the Carboniferous and Permian with an evolutional process of early compression and late extension. Mineralization of gold and other metals in the Junggar orogen occurred mainly in the Permian and in a few cases in the Late Carboniferous. The deposits are largely distributed in areas where collisional orogenesis was intensive and formed in a transitional stage from compression to extension. Therefore, gold mineralization in the Junggar orogen is fully consistent with the collisional orogenesis in time, space and geodynamic setting. This indicates that the mineral deposit model of collisional orogenesis is applicable to prospecting and study of ore deposits in the Junggar orogen. Furthermore, the factual distribution of gold and other deposits in this region is just the same as the collisional orogenic model presents.

The Tieluping silver deposit, which is sited along NE-trending faults within the high-grade metamorphic basement of the Xiong'er terrane, is part of an important Mesozoic orogenic-type Ag-Pb and Au belt recently discovered. Ore formation includes three stages: Early (E), Middle (M) and Late (L), which include quartz-pyrite (E), polymetallic sulfides (M) and carbonates (L), respectively. The E-stage fluids are characterized by δD=−90‰, δ13Cco2=2.0‰ and δ18O=9‰ at 373°C, and are deeply sourced; the L-stage fluids, with δD=−70‰, δ13CCo2=−1.3‰ and δ18O=−2‰, are shallow-sourced meteoric water; whereas the M-stage fluids, with δD=−109‰, δ13CCo2=0.1‰ and δ18O=2‰, are a mix of deep-sourced and shallow-sourced fluids. Comparisons of the D-O-C isotopic systematics of the E-stage ore-forming fluids with the fluids derived from Mesozoic granites, Archean-Paleoproterozoic metamorphic basement and Paleo-Mesoproterozoic Xiong'er Group, show that these units cannot generate fluids with the measured isotopic composition (high δ18O and δ13C ratios and low δD ratios) characteristic of the ore-forming fluids. This suggests that the E-stage ore-forming fluids originated from metamorphic devolatilization of a carbonate-shale-chert lithological association, locally rich in organic matter, which could correspond to the Meso-Neoproterozoic Guandaokou and Luanchuan Groups, rather than to geologic units in the Xiong'er terrane, the lower crust and the mantle. This supports the view that the rocks of the Guandaokou and Luanchuan Groups south of the Machaoying fault might be the favorable sources. A tectonic model that combines collisional orogeny, metallogeny and hydrothermal fluid flow is proposed to explain the formation of the Tieluping silver deposit. During the Mesozoic collision between the South and North China paleocontinents, a crustal slab containing a lithological association consisting of carbonate-shale-chert, locally rich in organic matter (carbonaceous shale) was thrust northwards beneath the Xiong'er terrane along the Machaoying fault. Metamorphic devolatilization of this underthrust slab provided the ore-forming fluids to develop the Au-Ag-(Pb-Zn) ore belt, which includes the Tieluping silver deposit.

The Dongchuang gold deposit in the Xiaoqinling are is an orogenic-type lode gold deposit. It is one of the few superlarge (>100 t Au) deposits in China. Although it has been argued that it was formed in the Mesozoic, related isotopic age data have not been reported in previous studies. Based on detailed geological study, the authors have carried out isotopic dating on various metallogenic generations. The ore-forming process of the Dongchuang gold deposit consists of four stages: coarse-grained pyrite-bearing quartz veins (stage I), fine-grained pyrite-quartz veinlets (stage II), multi-sulfides (stage III) and carbonate-quartz veinlets (stage IV). Ar-Ar dating on mineral separates of stages I, II and III yields plateau ages of 142.9±2.9 Ma, 132.2±2.6 Ma and 128.3±6.2 Ma, respectively. Sericite separates from stage II assemblage also yield an Ar-Ar isochron age of 132.6±2.7 Ma, similar to the Ar-Ar plateau age. These results suggest that the Dongchuang gold deposit was mainly formed during 143–128 Ma, coinciding with the authors' geological observations and previous hypothesis. This ore formation is coeval with the regional-tectonic transition from collisional compression to extension, strongly showing that the decompression-geothermal increase regime during compression-to-extension transition is the most conducive geodynamic environment to orogenic-type gold mineralization.