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Plate subduction plays a decisive role in continental tectonics, and subduction history is closely connected to deformation and sedimentation in the overriding plate. When and how the Paleo-Pacific Plate subducted beneath Southeast China in the Mesozoic is debated. Here, we show that provenance data, including detrital composition point counts, palaeocurrent data, and detrital zircon U-Pb geochronology from basins in Southeast China, record the timing and process of Paleo-Pacific Plate subduction during the Jurassic and Earliest Cretaceous. The U-Pb dating of detrital zircons from Jurassic samples indicates that the sediments were transported from multiple sources, including intracratonic mountains, tectonic belts and the inferred active continental margin arc that resulted from Paleo-Pacific Plate subduction. The clastic composition and U-Pb dating of Early Cretaceous tuffs suggest that they were sourced from nearby magmatic rocks and the eastern inferred magmatic arc. Based on detrital zircon U-Pb dating, igneous rock isotope, sedimentary, and structural data, we infer that an active continental magmatic arc developed along the coast of Southeast China in the Early Jurassic to Early Cretaceous (~200 Ma-135 Ma). The westward subduction of the Paleo-Pacific Plate initiated in the Early Jurassic (~200 Ma) and continued to the Early Cretaceous (~135 Ma). Paleo-Pacific Plate subduction resulted in the uplift of the northern Wuyi Mountain region and eastern South China and controlled the provenance characteristics of the sedimentary basins in Southeast China during the Jurassic to Early Cretaceous. [ABSTRACT FROM AUTHOR]

The Wangshi Group faithfully records the Late Cretaceous palaeogeographic environment and tectonic evolution of the East Asian continental margin. Here, we reconstruct a four-stage evolution model of the Late Cretaceous source-to-sink system in the northern Jiaolai Basin by multiproxy provenance methods. With statistical and visualization analyses of multiple results and comparisons to the characteristics of potential source regions, the results strongly suggest that (1) the Linjiazhuang Formation (Fm) was mainly sourced from the Qingshan Group volcanic rocks; (2) during the deposition of the Xingezhuang Fm, the Sulu orogenic belt south of the basin was rapidly uplifted and replaced the Qingshan Group volcanic rocks as the primary source area for the basin; (3) during the deposition of the Hongtuya Fm, the tectonic activity on the southern side of the basin weakened, and the Jiaobei area and Qingshan Group volcanic rocks again became primary sources for the basin; and (4) the Jingangkou Fm was sourced mainly from the Jiaobei terrane instead of the Qingshan Group volcanic rocks. The significant change in the main source region of this source-to-sink system during the deposition of the Xingezhuang Fm, from the Jiaobei terrane to the north to the Sulu orogenic belt to the south, suggests that the Sulu orogenic belt experienced rapid uplift in the early Late Cretaceous. The NNW subduction of the western Pacific Plate during the Late Cretaceous may have led to N-S extension in the East Asian continental margin, controlling the deposition of the Wangshi Group in the Jiaolai Basin and inducing the rapid uplift of the Sulu orogenic belt in the early Late Cretaceous. [ABSTRACT FROM AUTHOR]

The Triassic-Jurassic stratigraphy in the Yanshan fold-thrust belt is dominated by nonmarine deposits, and the division of this stratigraphy remains controversial among geologists. Age results from biostratigraphic and isotope chronological studies are inconsistent, especially for the Dengzhangzi and Guojiadian Basins in the eastern part of the Yanshan belt. We present four new detrital zircon U–Pb isotope datasets for the Triassic-Jurassic stratigraphic units and one for the Permian unit in the basins. The geochronological results show that the andesitic breccia in the Permian strata was deposited at ca. 273.78 ± 1.68 Ma, the Laohugou Formation was deposited in the Anisian-Ladinian Stage, the andesitic lava in the Shuiquangou Formation erupted at ca. 238.56 ± 0.91 Ma, and the conglomerate in the Guojiadian Formation was deposited from ca. 170 ± 5 to 163.0 ± 2.2 Ma. Field observations and facies analyses demonstrate that the Laohugou, Shuiquangou and Dengzhangzi Formations predominantly consist of subaqueous debris flow deposits, subaerial fluvial deposits, and fan delta deposits while the Guojiadian Formation is generally composed of fluvial and subaerial mass-flow deposits that formed in braided channels. Here, we propose a more precise and comprehensive Triassic-Jurassic stratigraphic division scheme based on age constraints and facies analysis. With this new stratigraphic sequence, we compare the Mesozoic stratigraphic units in the study area with those in other basins in the Yanshan fold-thrust belt in terms of the lithological associations, regional unconformities and zircon U-Pb dating results. This comparison indicates that the Indosinian and Yanshanian movements exerted a far-reaching influence on the development and evolution of the Dengzhangzi and Guojiadian Basins in the study area, forming several important regional unconformities and syntectonic conglomeratic units. These new age data on the stratigraphy are of fundamental significance for understanding the Mesozoic tectonic evolution of Yanshan. [ABSTRACT FROM AUTHOR]

Fluid dynamical and numerical modelling predicts a large-scale regional domal uplift prior to basalt eruptions in large igneous provinces, which can be readily measured when a plume head rises below a shallow marine sedimentary basin. Research on the sedimentology, biostratigraphy, and isotopic chronology of the Emeishan large igneous province demonstrates that the sedimentary environment in the Maokou stage is not uniform carbonate platform facies, but rather sedimentary facies with a north–south linear alignment and west–east different distribution controlled by the syn-depositional normal faulting of the Changhai and Xiaojiang faults, which are the result of underwater dynamic uplift induced by deep mantle activity. The dynamic uplift started in the Maokou stage. Thus, thinning of the Maokou limestone was the product of the difference in the initial depositional thickness caused by the underwater uplift and post-depositional surface uplift and erosion, but post-depositional uplift was much less than kilometre scale. Sedimentary facies differentiation and tectonic–sedimentary evolution in the Maokou stage provide a constraint for the time of the initial eruption and eruption environment before and during the Emeishan basalt eruption. Small-scale magmatic activity might have already begun in the middle of the Maokou stage, whereas submarine and terrestrial sedimentary environments coexisted before and during Emeishan basalt eruption. [ABSTRACT FROM PUBLISHER]