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• The maximum depositional age of the Suoi Chieng Formation is 1769 Ma. • The U-Pb age and Hf isotopes indicate sources originate from local basement rocks and the Rae craton of North Laurentia. • Distinct crustal evolutionary histories for the SW Yangtze and N Yangtze before their assembly in the late Paleoproterozoic. • The Yangtze Block was situated between southern Siberia and northern Laurentia within Nuna supercontinent. New U-Pb ages and Hf isotopic data for detrital zircons from the late Paleoproterozoic sedimentary rocks (Suoi Chieng Formation) in the Phan Si Pan Zone of northwest Vietnam constrain their depositional ages, provenance, and tectonic setting. The weighted average age of the youngest coherent zircon population is 1769 ± 31 Ma (MSWD = 1.3, n = 8), which provides a maximum depositional age for the Suoi Chieng Formation. The detrital zircons obtained from six Paleoproterozoic samples exhibit various ages, showing multiple magmatic and metamorphic events. The detrital zircon age pattern shows that magmatic activities in the source areas occurred at 2650 Ma, 2350–2150 Ma, and 2050 Ma, as well as minor activities at 2850 Ma, 1850 Ma, and 1780 Ma. Additionally, a prominent metamorphic age peak is observed around ca. 1850 Ma, while a few metamorphic zircons exhibit ages ranging from 2600 to 2500 Ma and 2100 Ma. This pattern indicates that the primary source of these zircons is the local basement rocks of the Phan Si Pan Zone and SW Yangtze. However, contributions from other adjoining cratonic blocks are also possible and these likely included the Rae craton of North Laurentia. Our new data verifies and expands earlier results, showing that the SW Yangtze and north Yangtze have distinct Archean-Paleoproterozoic crustal evolutionary histories prior to their assembly in the late Paleoproterozoic. Regional correlations based on detrital zircon spectra, stratigraphic and tectono-thermal histories show strong similarities between the SW Yangtze and the Rae craton of north Laurentia throughout the Paleoproterozoic, suggesting the proximity of the two blocks before or during the formation of the Nuna supercontinent. We further suggest that the north Yangtze adjoined southern Siberia in the Archean to late Paleoproterozoic as supported by their identical tectono-thermal histories and detrital zircon age spectra. In combination with published data, we propose that the Yangtze Block was located between north Laurentia and south Siberia during the Nuna assembly. [ABSTRACT FROM AUTHOR]

• Ca. 2.30–2.27 Ga, 1.85–1.83 Ga, and 1.75 Ga granitoids in the Phan Si Pan Complex, north Vietnam. • The two older episodes of granitoids formed by partial melting of Archean basements. • The ca. 1.75 Ga trondhjemite formed by partial melting of juvenile crust. • The Yangtze Block was located between southern Siberia and northern Laurentia within Nuna. There is no consensus on the Precambrian paleogeographic reconstructions of Yangtze Block through the various supercontinent cycles and its linkage to other continental blocks. New data on the Paleoproterozoic tectonic history of the block enables linkage with other major Nuna-forming continents to be constrained. Zircon U-Pb-Hf isotopic and whole-rock elemental data highlight three episodes of Paleoproterozoic granitoids, dated at 2.30–2.27 Ga, 1.85–1.83 Ga, and 1.75 Ga from the Phan Si Pan Complex of the Phan Si Pan Zone, a southeast extension of the Yangtze Block in north Vietnam. The older two episodes of granitoid emplacement have negative ε Hf(t) values with similar T DM2 ages of 3.3–2.9 Ga, which suggest reworking of Archean basement rocks possibly at syn- to post-collisional settings. The 1.75 Ga A-type trondhjemite with positive ε Hf(t) values (0 to + 9) formed by partial melting of Paleoproterozoic juvenile crustal materials along with some mantle addition, most likely related to an intra-plate rift setting. Integrating the new results with compilations throughout the Yangtze Block, we suggest that the northern and southwestern Yangtze have different Archean and earliest Paleoproterozoic histories. Furthermore, correlations of Archean-Paleoproterozoic tectono-thermal and detrital zircon signatures between southwestern Yangtze and north Laurentia, and between northern Yangtze and southern Siberia, suggest they were close neighbors at these times. The collision between the northern and southwestern Yangtze in the late Paleoproterozoic is inferred to have led to the assembly of Laurentia and Siberia along a cryptic suture in central Yangtze and widespread crustal magmatism. Thus, we tentatively reconstruct the Yangtze Block as a key tie point between northern Laurentia and southern Siberia within the Nuna Supercontinent. [ABSTRACT FROM AUTHOR]