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The kinematics of plate tectonics, deformation, and dynamic topography are strong indicators of coupling between plates and the mantle. East Asia is characterized by the presence of an unusually large horizontal slab that lies within the mantle transition zone. How this feature evolved and is linked to plate tectonics, deformation, and topography is poorly understood. Here, we show four‐dimensional geodynamic modeling results constrained by a new deforming plate reconstruction that fits mantle architecture inferred from seismic tomography. We find that the subducted western Pacific slab was progressively torn by the Philippine Sea plate rotating clockwise during the Miocene and that northwestward mantle flow contributed to shaping the horizontal slab during subduction, leading to dynamic subsidence along the East Asia margin. The rather subdued change in dynamic topography, predicted from those models that fit the horizontal slab in the mantle, is consistent with the variation in residual topography, recorded in the stratigraphy, within only about ±200 m over the last 50 Myr during a period of no large marine inundation or retreat. The tectonics and topography of East Asia strongly contrast with those of Southeast Asia and are reflective of slabs ephemerally stagnating in the mantle below East Asia while avalanching into the lower mantle below Southeast Asia. Key Points: Trench‐trench‐trench triple junction shift‐induced tearing of the Pacific slab and contributed to shaping the horizontal slabThe dynamic topography fits with variation in residual subsidence by approximately ±200 m over the last 50 MyrThe subdued topography of East Asia was a response to stagnant slabs in the mantle [ABSTRACT FROM AUTHOR]

A well‐constrained plate deformation model may lead to an improved understanding of sedimentary basin formation and the connection between subduction history and over‐riding plate deformation. Building quantitative models of basin kinematics and deformation remains challenging often due to the lack of comprehensive constraints. The Bohai Bay Basin (BBB) is an important manifestation of the destruction of the North China Craton, and records the plate kinematic history of East Asia during the Cenozoic. Although a number of interpretations of the formation of the BBB have been proposed, few quantitative basin reconstruction models have been built to test and refine previous ideas. Here, we developed a quantitative deformation reconstruction of the BBB constrained with balanced cross‐sections and structural, stratigraphic and depositional age data. Our reconstruction suggests that the basin formation process was composed of three main stages: Paleocene‐early Eocene (65–42 Ma) extension initiation, middle Eocene‐early Oligocene (42–32.8 Ma) extension climax and post‐Oligocene (32.8–0 Ma) post‐extensional subsidence. The deformation of the BBB is spatially heterogeneous, and its velocity directions rotated clockwise during the basin formation process. The reconstruction supports the interpretation that the BBB formed via strike‐slip faulting and orthogonal extension and that the basin is classified as a composite extensional‐transtensional basin. We argue that the clockwise rotation of the basin velocity field was driven by the counter‐clockwise rotation in the direction of Pacific Plate subduction. The kinematics of the BBB imply that the Pacific Plate may have been sufficiently coupled to the over‐riding East Asian Plate during the critical period of Pacific Plate reorganization. The new reconstruction provides a quantitative basis for studies of deformation processes not only in the vicinity of the BBB, but also more broadly throughout East Asia. [ABSTRACT FROM AUTHOR]

Detrital zircon geochronology and geochemistry have become the primary methods for reconstructing the Earth's tectonic and surficial processes over geologic time. The compilation and dissemination of detrital zircon data are essential to facilitate rapid, innovative, and reliable studies and to drive new research discoveries. To this end, we present EaDz, a new web-based, relational database for detrital zircons from East Asia, which includes geochronological, geochemical, petrological, and stratigraphic datasets. The EaDz currently contains 7083 rock samples representing 570,092 U–Pb ages, 77,394 Lu–Hf isotopes, 35,045 trace elements, and 1773 oxygen isotope data entries. Within the EaDz database, 71% of the samples are siliciclastic rocks, followed by 16% metasedimentary rocks, 6% modern sediments, and 7% other rocks. The database is intended to serve as a repository for new and existing detrital zircon data and a platform for the visualization and analysis of detrital zircon data. Through a publicly accessible interactive website, EaDz allows simultaneous data retrieval, analysis, and visualization in the cloud. Additionally, EaDz provides a means for combining the detrital zircon data with global plate reconstruction models - thus providing deep-time dynamic reconstructions of detrital palaeolocations. As such, the EaDz provides a powerful resource for applications in paleogeography reconstruction, plate tectonic reconstruction, and crustal-mantle evolution. The database will continue to be developed and improved. We encourage users to collaborate on data compilation by submitting data through the website or contacting corresponding authors directly after their data is published. • A web-based, relational database for detrital zircons from East Asia is presented • EaDz compliles geochronological, geochemical and stratigraphical data of East Asia • EaDz offers the most popular visualization and analysis tools for detrital zircon data • The EaDz database will continue to be developed and improved [ABSTRACT FROM AUTHOR]

East Asia and South America have both experienced long-term subduction since at least the Jurassic, but they have had contrasting tectonic evolutions since the Late Cretaceous. East Asia was dominated by extensional tectonics with many marginal sea basins forming during the Cenozoic while South America was dominated by compressional tectonics building the Andean mountains. The mechanism controlling this contrast in tectonic style on opposite sides of the Pacific has been unclear. We suggest that the deep mantle flow revealed by seismic tomography, plate reconstructions, and geodynamic models contributed to the pan-Pacific tectonic disparity. Our geodynamic models suggest that the Atlantic Ocean opening plays an important role in promoting compression-dominated tectonics and Andean building along the South American margin by allowing fast trench-ward motion of South America. On the other hand, the long-standing downwelling flow beneath the interior of Asia since Asian assembly in the Paleozoic and the early Mesozoic helps to inhibit Atlantic-type ocean opening in Asia and restrain trench-ward motion of East Asia, promoting extension-dominated tectonics along the Asian margin. The restrained trench-ward motion suggests a low probability of flat-slab subduction occurrence in East Asia during the late Mesozoic. • South Atlantic Ocean opening allows fast trench-ward motion of South America. • Atlantic Ocean opening promotes compression-dominated South America tectonics. • Slow trench-ward continental motion promotes extension-dominated East Asia tectonics. • Long-standing downwelling flow beneath Asia inhibits Atlantic-type ocean formation. • Low possibility of flat-slab subduction beneath East Asia during the late Mesozoic. [ABSTRACT FROM AUTHOR]