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[Display omitted] • Grenville-age terrane is identified in the Qilian orogen. • The Precambrian basement of the Qilian orogen is divided into four distinct mega-sequences. • ∼475 Ma metamorphism was related to the subduction of the Proto-Tethys Ocean. The Qilian orogen at the northeastern margin of the Tibetan Plateau records a complete history from continental breakup to oceanic basin evolution and back to continental collision during the Neoproterozoic to Paleozoic interval. The Qilian Ocean, as a branch of the Proto-Tethys Ocean, was connected to the Iapetus Ocean but is lesser known than its two more famous counterparts. This paper presents zircon U-Pb and biotite-muscovite 40Ar/39Ar isotope data from the Yemananshan Complex in the western Central Qilian belt to assess the age and provenance of late Mesoproterozoic-early Paleozoic successions in the Qilian orogen. The results indicate the Central Qilian belt is characterized by Late Mesoproterozoic-early Neoproterozoic orogenesis with magmatism from 1200 Ma to 900 Ma and clastic metasedimentary rocks deposited between 1050 and 920 Ma. Statistical analysis of detrital zircon data and auxiliary temporal information from the Qilian orogen affirms the notion that sedimentation occurred in four distinct megasequences: (1) 1950–1850 Ma, the oldest known strata, (2) 1250–920 Ma, during Grenvillian-Sveconorwegian orogenesis, (3) 840–760 Ma, the disintegration of Rodinia, and (4) 650–550 Ma, which is typical of the orogenic belts that sutured the Gondwana continental blocks. Metamorphic zircon and 40Ar/39Ar isotope data indicate early Paleozoic metamorphism at ca. 475 Ma, which overlaps with magmatic activity associated with arc-back-arc basin development in the Central Qilian belt, which was associated with subduction of the Proto-Tethys in eastern Gondwana. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ca. 311 Ma granite was derived from biotite dehydration melting of metagreywacke. • The ca. 283 Ma granite experienced extreme differentiation and melt–fluid interaction. • The granitic rocks record the tectonic transition from syn- to post-collision (ca. 320–280 Ma). • Hf isotopic mapping reveals significant crustal reworking. Peraluminous granitoids can provide crucial insights into crustal reworking. Here we report a geochemical study of two Late Paleozoic peraluminous granitic plutons in the South Tianshan Belt, NW China, to constrain their crustal reworking history. Zircon U-Pb analyses yield ages of 311 ± 4 Ma for the garnet-bearing biotite granite and 283 ± 4 Ma for the garnet-bearing muscovite granite. The garnet-bearing biotite granites exhibit peraluminous affinity (ASI = 1.04–1.11), high CaO/Na 2 O, low Rb/Sr, and negative ε Nd (t) (−8.7 to –7.5) and zircon ε Hf (t) (–8.4 to –0.8) values with ancient crustal model ages, which suggest they were derived from dehydration melting of metagraywacke. The garnet-bearing muscovite granites, containing manganese garnet, show high SiO 2 (72.3–76.8 wt%) and strongly peraluminous (ASI = 1.14–1.22), high Rb/Sr (37.8–128.9), low Zr/Hf (16.61–31.80) and Nb/Ta (3.05–5.71), and exhibit tetrad REE patterns (TE 1 , 3 = 1.05–1.27), which can be ascribed to high-degree fractional crystallization accompanied by the interaction with fluids. They show negative ε Nd (t) values (–8.6 to –6.6) and variable zircon ε Hf (t) values (–4.9 to +2.7), implying ancient crustal with minor juvenile crustal sources. In combination with the occurrence of peraluminous magmatic rocks of the South Tianshan Belt, we propose that the peraluminous magmatic rocks were formed by the partial melting of ancient crustal rocks from the passive continental margin of the Tarim Craton, which represents an important crustal reworking event in the Central Asian Orogenic Belt. [ABSTRACT FROM AUTHOR]