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The Erlian Basin is one of the largest intracontinental Meso-Cenozoic basins in Northeast China. The basin is filled with extra-thick Cretaceous sediments and offers unique opportunities to untangle the Late Mesozoic intraplate deformation in East Asia. However, despite decades of petroleum exploration in the basin, the Early Cretaceous chronostratigraphy and structural evolution of the Erlian Basin have been poorly studied. Based on newly obtained zircon U-Pb geochronological data, well lithological logs, and seismic reflection profiles, the present study carries out a detailed analysis of the tectonostratigraphic evolution of the Erlian Basin during the Early Cretaceous. The depositional ages of the Lower Cretaceous strata in the basin are refined, and the Early Cretaceous evolution of the basin is reestablished. The Lower Aershan, Upper Aershan, Lower Tenggeer, Upper Tenggeer, and Saihan formations are constrained to the middle Valanginian (ca. 138–135 Ma), late Valanginian (ca. 135–133 Ma), Hauterivian–early Aptian (ca. 133–121 Ma), middle Aptian (ca. 119–115 Ma), and latest Aptian–Albian (post ca. 115 Ma), respectively. The Early Cretaceous syn-rift subsidence of the basin was intermittent rather than continuous, and was punctuated by multiphase contractional deformation during the earliest Cretaceous (prior to ca. 138 Ma), middle Valanginian (ca. 135 Ma), latest Valanginian (ca. 133 Ma), middle Aptian (ca. 120 Ma), late Aptian (ca. 115 Ma), and Early/Late Cretaceous boundary. We tentatively attribute the extensional and contractional deformation in the Erlian Basin to a series of continental collisions along Asian margins: Karakoram-Lhasa/Qiangtang collision, Kolyma-Omolon/Siberia collision, Siberia/Amuria collision, Chukotka/Kolyma-Omolon collision, West Philippines/South China collision, and Okhotomorsk/East Asia collision. Image 1 • Depositional ages of the Lower Cretaceous strata of the Erlian Basin are refined. • Early Cretaceous tectonostratigraphic evolution of the Erlian Basin is established. • Early Cretaceous extension in Erlian Basin was intermittent rather than continuous. • Multiphase Early Cretaceous contractional deformation occurred in Erlian Basin. • Geodynamic origin of the extensional/contractional events in the basin is proposed. [ABSTRACT FROM AUTHOR]

Investigating the tectonostratigraphic evolution of Late Mesozoic basins in NE China and its surrounding areas offers great opportunities to restore the Late Mesozoic evolution of intraplate tectonic stress regime in East Asia and to uncover the relationships between intraplate deformation and plate margin tectonic processes. This study provides a comprehensive analysis of the stratigraphic and structural evolution of the basins in NE China and its surrounding areas during the Late Mesozoic. It is shown that these basins underwent significant extension and syn -rift subsidence during the Late Jurassic–Early Cretaceous. However, the long-lived extension was intermittent rather than continuous, and at least three pulses of short-lived episodic compressive deformation, that occurred at the latest Jurassic–earliest Cretaceous, middle Aptian (ca. 120 Ma), and late Aptian (ca. 115 Ma), could be recognized. The Late Jurassic–Early Cretaceous extension was terminated by a strong contractional event at the earliest Late Cretaceous. The frequent switches in regional tectonic stress regime between extension and contraction require a new tectonic interpretation, as proposed here. We suggest that during the Late Jurassic–Early Cretaceous, the continental collision and subsequent northeastward indentation of the Karakoram-Lhasa Block with the southern Asian margin probably activated a significant strike-slip fault system, propagating approximately from the collision zone to the eastern Asian margin, and drove East Asia into a lateral extrusion/escape tectonic setting. The activated strike-slip faulting probably triggered the postorogenic gravitational collapse of the thickened upper crust and the delamination of the lower crust and mantle lithosphere, resulting in regional extension and intense magmatism in East Asia during the Late Mesozoic. The intercurrent multiphase short-lived contractional events were likely associated with a series of continental collision events along Asian margins. The latest Jurassic–earliest Cretaceous contractional deformation probably resulted from the combined effects of the closure of the eastern Mongol-Okhotsk Ocean, the Kolyma-Omolon/Siberia collision, and the Karakoram-Lhasa/Southern Asia collision. The middle Aptian contractional deformation probably resulted from the Proto-Kurosegawa/Eastern Asia collision. The late Aptian contractional deformation probably resulted from the Chukotka/Kolyma-Omolon collision. The earliest Late Cretaceous contractional deformation probably resulted from the Okhotomorsk/Eastern Asia collision. [Display omitted] • Documents the Late Mesozoic tectonostratigraphic evolution of basins in NE China and its surrounding areas. • Restores the Late Mesozoic evolution of regional tectonic stress regime in NE China and its surrounding areas. • Proposes an explanation for the Late Mesozoic regional extension and contraction in East Asia. • Provides an explanation for the destruction of North China Craton during the Late Mesozoic. [ABSTRACT FROM AUTHOR]

Mallotus japonicus is a shrub species in the family of Euphorbiaceae. The study of plastome would be helpful for its phylogenetic study and species identification. The total length of complete plastome for Mallotus japonicus is of 164,912 bp, with typical part-four structure and gene content of angiosperm plastome, including two inverted repeat (IR) regions of 27,829 bp, a large single-copy (LSC) region of 90,319 bp, and a small single-copy (SSC) region of 18,935 bp. The plastome contains 125 genes, consisting of 80 unique protein-coding genes, 31 unique tRNA gene, four unique rRNA genes (5S rRNA, 4.5S rRNA, 16S rRNA, and 23S rRNA), and five pseudogenes. The overall G/C content in the plastome of Mallotus japonicus is 40.2%. The phylogenetic analysis indicates that M. japonicus is closer to M. peltatus than other species in this study. The complete plastome sequence is conducive to the exploitation and utilization of Euphorbiaceae resources and the phylogenetic study in future. [ABSTRACT FROM AUTHOR]