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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.

The Qinling Orogen is located between the North China and South China blocks, and considered to form by the multiple accretionary processes, being also characterized by development of voluminous magmatic intrusions as well as abundant mineral resources. Here we compile the geological, geochemical and geochronological data of the Early Mesozoic granitoids from the Qingling Orogen and attempt to constrain the Early Mesozoic tectonic evolution and mechanism of gold mineralization in this region. The Early Mesozoic granitoids are most widespread in the Qinling Orogen, especially in western part, and can be classified into S‐, I‐, I‐A‐types, with the I‐type constituting the major variety. The isotopic ages of the three types granitoids are 200–222 Ma, 185–248 Ma, 210–227 Ma, respectively, indicating overlapping ages with a wide span of I‐type granitoids. The S‐, I‐, I‐A‐type granitoids show obvious zonation characteristics, that is the S‐type granitoids only occurred in southern South Qinling Belt, the I‐type granitoids are most widespread in the western Qinling Orogen, and the I‐A‐type granitoids are mainly exposed in the North Qinling Belt. The S‐type granitoids crystallized at relatively low temperature (800–850 °C) and deep‐crustal level (ca. 8 kb) and derived mainly from partial melting of a clay‐poor psammitic source. The I‐type granitoids formed at high temperature (>925 °C) and pressures above the garnet‐in phase boundary (>1.2 GPa) and derived from greywackes and partially igneous source. Moreover, the I‐A‐type granitoids probably derived from distinct sources with sufficient interaction, or common origin but underwent different degrees of crustal contamination, and generated at high temperatures (ca. 950 °C) and low pressures (1.0–0.2 GPa) conditions. These features indicate the Qinling Orogen experienced subduction, syn‐collisional, and post‐collisional during the Early Mesozoic, and also suggest the S‐, I‐, I‐A‐types granitoids underwent an episodic growth documenting the tectonic regime switchover at this stage. The gold deposits in the western Qinling Orogen can be classified as orogenic, Carlin‐type, and Carlin‐like gold deposits with the formation age of Late Triassic. The orogenic and Carlin‐type gold deposits have no genetic relation to granitic magmatism, but the Carlin‐like gold deposits is related to the synchronous magmatism. Combined with regional geology and metallogenic systems, we suggest that the multi‐stage Qinling Orogenesis resulted in the formation of the Early Mesozoic S‐, I‐, I‐A‐type granitoids and different types of gold deposits with some characteristic differences.

The Devonian volcanic rocks are widely distributed in the East Junggar (Xinjiang, NW China), preserving important magmatic records for investigating Palaeozoic tectonic evolution. The Beitashan Formation is mainly composed of pyroclastic rocks and sedimentary rocks in the lower section and intermediate–basic volcanic lava and pyroclastic rocks in the upper section. In this paper, we present geochronological, geochemical, and in situ Lu–Hf isotopic data for Beitashan Formation volcanic rocks from the East Junggar. Zircon U–Pb analyses from a basalt sample by laser ablation inductively coupled plasma mass spectrometry yielded a weighted mean age of 387.8 ± 4.5 Ma, indicating that it was generated in the Middle Devonian. The basic–intermediate volcanic rocks are tholeiitic to calc‐alkalic and are characterized by MgO (2.29–5.91 wt.%), low TiO2 (0.75–1.36 wt.%), and relatively high Al2O3 (15.82–16.73 wt.%). Furthermore, they display enrichment in light rare‐earth elements and large‐ion lithophile elements (such as Ba and Sr) and depletion in Nb, Ta, and Ti, along with slightly positive Eu anomalies (δEu = 0.83–1.15) and Ce anomalies (δCe = 1.00–1.11). In addition, in situ zircon Hf isotopic analyses from basalt samples show εHf(t) values ranging from +4.33 to +15.2, indicating a depleted mantle source with minor crustal contamination. They also show relatively low Nb/Zr (0.04–0.06), Th/Yb (0.67–3.83), and Ba/La (6.79–67.53) and high Ce/Th (7.71–18.94), Ba/Rb (21.39–294.28), and Ba/Th (31.42–486.58). The geochemical data suggest these rocks were likely derived from 10% to 30% partial melting of a garnet‐rich with minor spinel‐bearing Iherzolite depleted mantle metasomatized by slab‐derived fluids, with crustal contamination. Combined with the geological setting and previous studies, we suggest that the northern East Junggar was in a northward‐subducted island‐arc setting in the Devonian.