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In recent decades, the Yanshanian movement in the Mesozoic has been a hotspot of much geological research, attracting numerous studies focusing on regional tectonics, basin evolution, and associated magmatism and volcanic activities. The Haifanggou Formation, exposed in Xingcheng Basin, which is one of intracontinental basins in western Liaoning Province, North China Craton (NCC), comprises mainly conglomerates dominated with interbedded sandstone. Although palaeontology, stratigraphy and lithofacies have been established, its mineralogical compositions and geochronology, even the provenance and implications for Yanshanian movement are still poorly discussed. Available sandstone samples provided a unique opportunity to study the genesis and further deciphered the tectonic mechanisms. The sandstone types of Haifanggou Formation are dominantly litho‐feldspathic litharenite and litharenite. Modal sandstone analysis shows that the origin and deposition mainly are due to arid to semi‐arid weathering and recycling of older rocks and magmatic arcs, eroded and transported debris from eastern NCC. Our new detrital zircon U–Pb ages exhibit that the maximum depositional ages of the Haifanggou Formation were conservatively estimated as late Middle Jurassic (165.6 ± 3.1 Ma). The detrital zircon U–Pb age spectrum of this formation is dominated by several peaks that indicate a provenance from the surrounding rocks including the basement of NCC. The sedimentation of the Haifanggou Formation is deposited under compressional tectonics as a local response of the Yanshanian movement which was related to the subduction of Palaeo‐Pacific Plate. [ABSTRACT FROM AUTHOR]

The Yanshan Movement occurred mainly during the Middle-Late Jurassic, and gave rise to NE trending structures, magmatic events, volcanism and mineral resources. The transformation and evolution of the movement during the Middle-Late Jurassic were investigated from the rock assemblage, geochemistry, and chronology in adamellites which were exposed in the Xingcheng area, western Liaoning. Two types of adamellites were recognized—biotite adamellites with the formation age of 172–168 Ma and garnet-bearing adamellites of 158–152 Ma. All the samples of the two types of adamellites displayed enriched characteristics with high content of SiO2 (66.86–75.55 wt.%) and total alkali (Na2O + K2O = 7.56–8.71 wt.%), high large ion lithophile element (LILE: K, Rb, Sr), and low high field strength element (HFSE: Ce, Ta, P, Ti). The biotite adamellites belong to metaluminous-peraluminous I-type granites, and show volcanic arc granite characteristics, and were formed by partial melting of the ancient crust in the compressional setting that resulting from the subduction of the Paleo-Pacific plate beneath the north margin of the North China Craton (NCC). The garnet-bearing adamellites are also metaluminous-peraluminous I-type granites, with characteristics of both the compressional and extensional regimes, which were formed at the middle-late stages of the continuing subduction of the Paleo-Pacific plate, while simultaneously, the frontal side of the subduction slab began to roll back, leading to an extensional environment. Combining with regional geophysical studies and our petrological and geochemical studies, we propose that the eastern segment of the northern margin of NCC may have been controlled by the Paleo-Pacific tectonic domain at the latest in the Middle Jurassic, while the initiation of the tectonic regime from a compressional to an extensional environment was during the Late Jurassic (158–152 Ma) as a response of the Yanshan Movement. Simultaneously, geochronological statistics of the ore deposits in western Liaoning show that the Mesozoic endogenetic metalliferous deposits formed in a compressive environment influenced by the subduction of the Paleo-Pacific plate, similar to the magma events in ages, and the magmatism provided the thermodynamic condition and the source of metallogenic hydrothermal fluid for mineralization. [ABSTRACT FROM AUTHOR]