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Mantle convection plays a fundamental role in driving evolution of oceanic and continental lithosphere. In turn it impacts a broad suite of processes operating at or close to Earth's surface including landscape evolution, glacio‐eustasy, magmatism, and climate. A variety of theoretical approaches now exist to simulate mantle convection. Outputs from such simulations are being used to parameterize models of landscape evolution and basin formation. However, the substantial body of existing simulations has generated a variety of conflicting views on the history of dynamic topography, its evolution and key parameters for modeling mantle flow. The focus of this study is on developing strategies to use large‐scale quantitative stratigraphic observations to assess model predictions and identify simulation parameters that generate realistic predictions of Earth surface evolution. Spot measurements of uplift or subsidence provide useful target observations for models of dynamic topography, but finding areas where tectonics have not also influenced vertical motions is challenging. To address this issue, we use large inventories of stratigraphic data from across North America with contextual geophysical and geodetic data to constrain the regional uplift and subsidence history. We demonstrate that a suite of typical geodynamic simulations struggle to match the amplitude, polarity and timing of observed vertical motions. Building on recent seismological advances, we then explore strategies for understanding patterns of continental uplift and subsidence that incorporate (and test) predicted evolution of the lithosphere, asthenosphere and deep mantle. Our results demonstrate the importance of contributions from the uppermost mantle in driving vertical motions of continental interiors. Key Points: Large‐scale digital inventories of stratigraphic observations used to test predictions from mantle convection simulationsUseful diagnostics include net uplift and subsidence, absolute elevations, paleo‐water depthsUpper mantle thermo‐mechanical evolution—crucial for assessing sub‐plate support—constrained using stratigraphy [ABSTRACT FROM AUTHOR]

The flooding record of North America has been used to infer patterns of global erosion and sea level in deep time. Here, we utilize the geospatial dimension of the stratigraphic record provided by the Macrostrat database, and patterns of erosion from thermochronology, to resolve local tectonic subsidence from global sea level. We show that the flooding history of North America correlates in space and time with continentfacing subduction along active margins, consistent with subduction-driven dynamic topographic subsidence of the continental interior. Nonetheless, the continentally aggregated flooding signal of North America is an exaggerated global M-curve of Phanerozoic sea level. This coincidence relates to the closing of the geodynamic loop of the supercontinent cycle: Subduction under North America accommodated both the makeup and breakup of Pangaea, which, coupled with changing ridge length, flattened hypsometry, and increased sea level both locally and globally. The sole Phanerozoic exception to this pattern of global sea level tracking North American near-field geodynamics is the Cambrian Sauk transgression. We argue that this is a far-field record of the inception of circum-Gondwanan subduction, independent of North America, which significantly flattened Earth's hypsometry. This hypsometric flattening displaced ocean water globally, flooding tectonically passive North America to seal the Great Unconformity. [ABSTRACT FROM AUTHOR]

Global sea level change can be inferred from sequence stratigraphic and continental flooding data. These methods reconstruct sea level from peri-cratonic and cratonic basins that are assumed to be tectonically stable and sometimes called reference districts, and from spatio-temporal correlations across basins. However, it has been understood that long-wavelength (typically hundreds of km) and low-amplitude (<2 km) vertical displacements of the Earth's surface due to mantle flow, namely dynamic topography, can occur in the absence of crustal deformation. Dynamic topography can drive marine inundation or regional emergence of continents and must be taken into consideration for eustasy estimates. Our analysis indicates that the long-term trend in global-scale maximum flooding over the late Paleozoic generally correlates with global sea level curves. The first-order flooding history of North America correlates with some estimates of eustasy. The Paleozoic inundation of South America does not follow long-term sea level variations. The flooding lows during the Early Carboniferous and high during the Late Carboniferous are at odds with estimates of eustasy and can be explained by dynamic uplift and subsidence, respectively. Our dynamic topography models indicate that the Yangtze Platform of South China experienced significant dynamic subsidence during the transition from Permian to Triassic largely due to proto-Pacific subduction and its northward motion to collide with North China. The reference districts – Western New York, Oklahoma and Kansas, and West Texas in North America – were to some degree affected by dynamic uplift and subsidence associated with long-lived Panthalassa subduction zones, closure of the Rheic Ocean and large-scale upwelling above the African deep-mantle structure during late Paleozoic times. This indicates that some published global sea level curves may include non-eustatic signals such as dynamic uplift or subsidence. The interpretation of stratigraphic data gathered from these reference districts should be treated with caution to estimate global sea level variations. Unlabelled Image • First-order inundation of North America in the late Paleozoic correlates with eustasy. • Some patterns in flooding of South America can be explained by dynamic topography. • The South China reference district for global sea level was affected by mantle flow. • Dynamic topography should be considered to understand Paleozoic sea level change. [ABSTRACT FROM AUTHOR]

Abstract: The regional and continental scale dynamics of North America and vicinity are explored using a high-resolution model of mantle flow. The model is constrained by simultaneously inverting global seismic and mantle convection data sets and it includes an explicit treatment of the positive chemical buoyancy of the continental tectosphere. Moreover, it adopts a depth-dependent mantle viscosity structure which reconciles both glacial isostatic adjustment (GIA) and convection data. The flow model successfully reproduces plate velocities and observations of surface gravity and topography, including the continent-scale quasi-linear depression (after corrections for GIA and crustal heterogeneity) extending from northern Alaska to Venezuela. The predictions also match lithospheric flow and stress fields inferred from local and regional measurements of seismic anisotropy and surface deformation. We demonstrate that these signals are largely driven by viscous flow coupled to density anomalies in the deep portions of the upper mantle and within the lower mantle, where the latter may be associated with the descent of the ancient Kula–Farallon plate system and an active mantle upwelling below the Pacific margin of the North American plate. More importantly, the flow calculations elucidate how these large-scale heterogeneities give rise to regional-scale flow and stress patterns below the southwestern U.S. and below the central U.S. [Copyright &y& Elsevier]

The Colorado Plateau contains Late Cretaceous marine strata that are at a mean elevation of ~2 km. The timing and amount of uplift since the Cretaceous has generated considerable debate. With the exception of a few studies, topography supported by vertical stresses generated by viscous flow in the mantle has not been explicitly considered to contribute to the elevation of this region. Herein we compute the viscous flow beneath North America that is driven by density anomalies inferred from joint seismic-geodynamic modeling. We find that the Colorado Plateau overlies a strong mantle upwelling that is coupled to the sinking Farallon slab, currently beneath the eastern United States. Consequently, the Colorado Plateau is currently a focused dynamic topography high within the western U.S. Cordillera. Moreover, this strong upwelling impacts the base of the lithosphere at an oblique angle east of the plateau directly below the Rio Grande Rift. We attribute this flow as being responsible for some of the recent magmatic activity along the Jemez lineament as well as contributing to the recent rifting process in the Rio Grande Rift valley. [ABSTRACT FROM AUTHOR]