| Summary: | The paper examines a suite of low-grade metamorphosed carbonate-clastic rocks located in the southwestern Ordos Block of the western North China Craton (NCC), whose formation age and tectonic setting remain subjects of debated. Combining regional geological data with detrital zircon LA-ICP-MS U-Pb age spectra of the low-grade metamorphosed clastic rocks, the deposition age is constrained to 900–635 Ma (Neoproterozoic). As a result, these strata should be reclassified from their originally assigned Paleoprtoterozoic Xiong'er Group. The detrital zircon LA-ICP-MS U-Pb age spectra also indicate that the Ordos Block, North Qinling Orogenic Belt, and Longshan Tectonic Belt all served as source terrains for the clastic sediments. The rocks are characterized by intense structural deformation. Based on geochronological data, this study identifies three stages of structural deformation, each occurring at different tectonic levels during distinct periods: the early stage of the Early Paleozoic, the later stage of the Early Paleozoic, and the Early-Middle Triassic. These stages correspond temporally and spatially to orogenic events in the surrounding regions. These findings provide new evidence for the Paleo-Neoproterozoic tectonic evolution of the southwestern part of the NCC, as well as for polyphase orogenies during the Phanerozoic. The research also suggests that tectonic deformations at the convergence points of multiple tectonic units may preserve important geological records of orogeny in the surrounding areas.
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