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The Darbut tectono‐magmatic zone in the West Junggar terrane (NW China) is an important component of the famous Circum‐Balkhash‐West Junggar metallogenic province. In this region, the discovery of some small but high‐quality Cu–Au deposits/prospects indicate substantial exploration potential for large porphyry Cu–Au deposits, for example, those in the neighbouring Kazakhstan. In this contribution, we concluded that the Dulunhe granite and small ore‐bearing granitoids in Baogutu are adakitic petrogenesis, and the Buerkesitai and Tasikuola granites (formed by magma mixing) are well comparable with the Xiaerpu granite. In summary, granitoids with similar petrogenesis and mineralization are distributed on both sides of the Darbut fault zone and show good correlations with the sinistral movement of the latter. We propose that the porphyry Cu–Mo–Au mineralization potential of the small calc‐alkaline I‐type granitic stocks in southern West Junggar region is significantly higher than that of alkaline A‐type large granitic batholiths. Besides, the magma mixing‐derived and adakitic granites have great prospecting potentialities. We argue that the Cu–Mo–Au mineralization in the Darbut tectono‐magmatic zone was originally E‐W trending, and then displaced by the Darbut sinistral strike‐slip faulting, instead of being controlled by NE‐NNE trending faults. The main regional mineralization pattern comprises a northern magmatic‐hydrothermal Au belt (~318 Ma), a middle porphyry Mo belt (~296 Ma), and a southern adakite and magma mixing granite‐related Cu–Au belt (~313 Ma). We infer that the Bieluagaxi Au belt may continue eastward to east of Sartohay.

Late Carboniferous to Early Permian granitic rocks are widely distributed in the Western Junggar (Xinjiang, NW China), but their petrogenesis and tectonic contexts remain controversial. In this paper, we present new zircon U–Pb age, major element, trace element data for the Huangliangzi pluton from the southern West Junggar. The pluton mainly consists of granodiorite porphyry, biotite monzonitic granite porphyry, and quartz monzonite diorite porphyry. Laser‐ablation inductively‐coupled mass‐spectrometry (LA‐ICP‐MS) zircon U–Pb obtained the age of 321.7 ± 1.3 Ma, indicating the granodiorite porphyry was emplaced in the early Late Carboniferous, coeval with abundant magmatic rocks in the region. Geochemically, these rocks are moderately peraluminous high‐K calc‐alkalic and characterized by relatively high SiO2 (64.31–66.69 wt.%), Al2O3 (15.82–16.73 wt.%), and Sr (379–489 ppm) contents and low MgO (1.08–2.46 wt.%; Mg# = 39–55), Y (7.61–9.64 ppm), and Yb (0.95–1.23 ppm) contents, along with positive Eu anomalies (Eu/Eu* = 1.01–1.34) and high Sr/Y (47.7–57.1) ratios. These are compositional features of adakites that are commonly assumed to have been produced through partial melting of subducted oceanic crust. In addition, the adakitic rocks are relatively enriched in light rare‐earth elements (LREEs), large ion lithophile elements (LILEs: e.g., Rb, Ba, Sr, and K), and depleted in high‐field‐strength elements (HFSEs: e.g., Nb, Ta, and Ti) and are also characterized by high εNd(t) value and low initial (87Sr/86Sr)i ratio. The most plausible mechanism for the Huangliangzi adakitic porphyries is the partial melting of subducted oceanic crust interacting with a mantle wedge. Combined with the geological setting and previous studies, therefore, we suggest that the southern West Junggar was in a subduction‐dominated island‐arc setting in the early Late Carboniferous, and multistage subduction–accretionary orogeny may be the main mechanism for the difference between the north and the south subduction duration in the Western Junggar.

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The evolution of the Tethys Ocean is a significant geological event in global evolution history. However, although the hinterland of China has Tethyan sedimentary formations, the original extent of the Neo‐Tethyan Ocean remains vague and controversial. It has been confirmed that the Triassic strata in the Qinling Orogen is bounded by regional faults in the north and the south with an east–west‐trending distribution, as well as a scissor‐like linked to Paleo‐Tethyan flysch to the Bayakala area. The Qinling Orogen is characterized by great thickness and unique sedimentary formations, including deep‐water gravity flows, colluvial deposits, and olistostromes. Moreover, the Triassic strata have plastic rheology and buckling folds that are stronger than those of the adjacent pre‐Triassic strata in an aulacogen sedimentary setting. The original Yangtze‐type platform facies deposition in the Qinling rapidly switched into the Tethyan‐type aulacogen deposition after the Ladinian marine regression during the Middle Triassic. The Qinling Ocean was separated from the original and coeval Yangtze Ocean to the east and then connected with the Tethys Ocean to the west, and the orogeny started after the “emergency” closure of the basin during the late Middle Triassic to early Late Triassic. This unusual sedimentation and evolution highlight the uniqueness and complexity of the Qinling Tethyan‐type deposition. The Qinling Tethyan‐type Triassic formation is remarkably different from that of the Yangtze‐type platform facies Triassic formation in China recording the opening and closing of the Tethys Ocean within the mainland of China in the Triassic. The discovery and confirmation of the Triassic Tethyan‐type aulacogen sedimentation in the hinterland of China provide important evidence for further study of identification of the distribution and configuration of ocean and continent, and refinement and modification of the Tethyan Ocean of the global Triassic plate tectonic evolution.