The nature of the Precambrian basement in the Cathaysia Block of South China is controversial, which inhibits our understanding of the pre‐Devonian tectonic evolution of the region. In this study, a suite of amphibolites and marbles in northern Fujian area located in the north of the Cathaysia Block were subjected to LA–ICP–MS U–Pb zircon geochronological and geochemical analyses. Results show that the protolith of the amphibolite formed after ca. 459 Ma, and its metamorphism happened at ca. 429 Ma. The protolith of the marble was deposited after ca. 518 Ma, and its metamorphic age is ca. 437 Ma. The amphibolites are divided into two groups based on geochemical data. Group 1 has an OIB‐like feature that might have formed in an environment characterized by oceanic islands and seamounts. Magmas associated with Group 1 were derived from an enriched mantle source with OIB characteristics. The protolith of Group 2 shows IAB feature that formed in an island arc environment. Marbles are interpreted to represent metamorphosed marine carbonate rocks. Integration of geochronological and geochemical study indicates that the marble and amphibolite should be an early Palaeozoic oceanic island–seamount association. It suggests the Cathaysia Block underwent oceanic subduction during collisional orogenesis in the early Palaeozoic. This subduction is thought to have initiated prior to ca. 437 Ma. The U–Pb zircon ages of younger intrusive granites indicate that final amalgamation occurred before ca. 392 Ma. During this process, east and west Wuyi were amalgamated to form the unified Cathaysia Block. Thus, it suggests that there was no unified pre‐Devonian basement in the Cathaysia Block. The pre‐Devonian tectonic setting of the Cathaysia Block was an accretionary orogeny.

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We carried out an integrated study of zircon U-Pb geochronology, Hf isotopes and geochemistry on the paragneisses and amphibolites from the Chencai area, South China. The detrital zircon ages of four paragneisses range from 2974 to 501 Ma with the main peak at ca. 820 Ma. The detrital materials with Neoproterozoic age may derive from the Jiangnan Orogen and those of Palaeo-Mesoproterozoic age may come from the Wuyi terrane. The youngest age indicates that the protoliths of the

The North Qinling Orogen underwent subduction and collision processes during the Palaeozoic, but the tectonic framework remains unclear. To investigate the tectonic evolution of the North Qinling Orogen, we selected the Devonian granites from the northeastern margin of the North Qinling Terrane. Integrated petrographic, geochemical, and geochronological studies, as well as Sr-Nd-Hf isotopic analyses, were carried out on the newly identified Devonian granites from the Hengjian area in the northeastern North Qinling Terrane, Qinling Orogenic Belt. Zircon laser ablation inductively coupled plasma mass spectrometry U-Pb dating reveals that these granites were crystallized at 396-387 Ma. The granite samples are metaluminous to weakly peraluminous (A/CNK = Al 2 O 3 /(CaO+Na 2 O+K 2 O) = 0.86 to 1.12), with high SiO 2 (60.6-76.5 wt%) and high total alkaline (Na 2 O + K 2 O = 8.45-11.0 wt%) contents. The granites are enriched in Th, rare-earth element, Zr, and Hf and depleted in Sr, Nb, Ta, P, Eu, and Ti. They are characterized by high Zr + Nb + Ce + Y contents (511-990 ppm) and 10,000*Ga/Al ratios (2.71-3.32), as well as high zircon-saturation temperatures (T Zr = 819-885 C, average = 845 C), which indicate that they are typical A-type granites. The granites have low Y/Nb (0.39-0.67) and Yb/Ta (0.56-0.83) ratios, resembling those of the A 1 -type granite, which indicates that they are formed in anorogenic settings. They also have low ( 87 Sr/ 86 Sr) i ratios (0.7055-0.7071) and negative ε Nd (t) values (À10.1 to À8.40) and variable zircon ε Hf (t) values (À8.46 to +14.7), with the two-stage model ages of 2.0-1.8 Ga and 1.9-0.4 Ga, respectively. These geological features suggest that the granites of the Hengjian area were most likely generated by partial melting of mafic lower crust induced by asthenospheric ascent. The A-type granites were generated in a continental rift environment during 396-387 Ma, corresponding to the closure of the Shangdan Ocean and the opening of the Palaeo-Tethyan Ocean during the Early Devonian.