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Considerable controversy concerns the consumption and closure processes of the North and South Altyn Oceans resulting in the formation of the North Altyn Tagh subduction-accretion belt and the South Altyn Tagh subduction-collision belt in the Altyn Tagh orogen in southeastern Tarim. This study focused on U–Pb ages and Hf isotopes of detrital zircons from early Paleozoic sedimentary rocks in the Central Altyn Tagh terrane. Our dating results revealed that the studied sedimentary rocks were deposited at ca. 467–429 Ma. The predominant early Paleozoic detrital zircons demonstrate negative εHf(t) values, highlighting their derivation from the coeval intermediate-felsic magmatic rocks sourced from ancient supracrustal materials with enriched isotopes. These inferred, enriched intermediate-felsic magmatic rocks were probably generated in different consumption and closure processes of the North and South Altyn Oceans, based on geochronology and geochemistry of the early-middle Paleozoic intermediate-felsic magmatic rocks in the Altyn Tagh orogen. A number of ca. 520–490 Ma detrital zircons were primarily derived from the coeval, enriched intermediate-felsic magmatic rocks in the local Central Altyn Tagh terrane and the adjacent North Altyn Tagh subduction-accretion belt associated with the advancing subduction of the North Altyn Ocean. The ca. 490–470 Ma detrital zircons are most prominent and suggest a derivation from the coeval, enriched magmatic rocks subject to the rollback of the North Altyn Ocean. These inferred magmatic rocks might have once existed in the region but have been intensely exhumed to be source material for the studied sedimentary rocks. A few ca. 450 Ma detrital zircons indicate a provenance from the North Altyn Tagh subduction-accretion belt during collision after the final closure of the North Altyn Ocean. In contrast, some ca. 470–460 Ma detrital zircons were probably derived from the coeval intermediate- to felsic-magmatic rocks in the Central Altyn Tagh terrane during the exhumation stage of the deep continental collision after the final closure of the South Altyn Ocean. Combination of provenance study and magmatic record provides potential to establish complicated orogenic evolution. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Keketale Pb-Zn deposit was formed and was modified in ∼400 Ma and ∼265 Ma, respectively. • The original VMS hydrothermal system can be illustrated by magnetite petrology and geochemistry. • Magnetite has the potential to be an indicator of VMS mineralization. • The Keketale deposit witnessed the evolution of the Chinese Altai and the Paleo-Asian Ocean. The Keketale Pb-Zn deposit (KKTL deposit) is one of the largest VMS-type Pb-Zn deposits in the Altai Mountains, Central Asian Orogenic Belt. Field investigations and microscopic observations suggest that the evolution of the deposit can be divided into two major stages: syngenetic massive sulfide mineralization related to coeval volcanism and epigenetic polymetallic vein mineralization linked to metamorphism and deformation. Supported by the U-Pb dating of zircon and garnet of immediate host rocks (i.e. garnet biotite schist), the former occurred in ∼400 Ma during the Early Devonian, and the latter developed in ∼265 Ma during the Middle Permian. The original VMS hydrothermal system is varying in the physicochemical conditions (e.g., temperature, oxygen fugacity, and sulfur fugacity) in space, together with fluid-rock interactions, causing two types of magnetites with different compositions and textures in different sites. Furthermore, it is revealed that the spatial variations of temperature-sensitive elements (e.g., Ti and Sn) of magnetite can be used to find the location of the hydrothermal vent, which can serve to guide the regional prospecting. Modifications of the KKTL deposit are indicated by deformed sulfides, annealed sulfides, remobilized sulfides, and epigenetic polymetallic veins. We draw a conclusion that the KKTL deposit witnessed the evolution of the Chinese Altai and the Paleo-Asian Ocean, the syngenetic volcanic-associated VMS mineralization was linked with arc/arc-back tectonic setting caused by the subduction of the Paleo-Asian Ocean toward the Chinese Altai, and the modification of the KKTL deposit was related to the collision between the Chinese Altai and the Junggar Block, along with the closing of the back-arc basin. [ABSTRACT FROM AUTHOR]