| Summary: | It is known that deep Earth and surface processes are intimately linked across broad spatial-temporal scales, however, quantifying this interaction remains elusive. The emergence of coupled plate tectonic and mantle convection, “geodynamic,” models has been facilitated by recent advances in computational resources, numerical solutions of mantle flow and plate model resolution. Five absolute reference frames based on hotspot tracks, palaeomagnetic data and subducted slabs are compared, resulting in differences in plate boundary locations of up to 3000 km and in plate velocities of up to 10 cm/yr. Through a comparison to seismic tomography, differences in predicted mantle structure for features ~20,000 km wide are largely due to velocity variability, and are best reproduced in hotspot frames. Shorter wavelength differences (<4,000 km) are attributed to plate boundary locations and are best reproduced with hybrid hotspot-palaeomagnetic frames. The Jurassic-Cretaceous history of the circum-Arctic is one of the most poorly constrained realms in global plate reconstructions. A revised regional model since 200 Ma, with connected plate boundaries is presented, focusing on the opening and closing the South Anuyi and Oimyakon oceans, the Amerasia Basin and Panthalassa. Tomographic and geodynamic evidence for these oceans are found under present-day Greenland, Siberia and North America. The time-dependent models also suggest an alternative interpretation of the location and affinities of the “Farallon” and “Mongol-Okhotsk” slabs. A powerful outcome of geodynamic models is the evolution of dynamic topography. We suggest that at least 50% of the anomalously deep Argentine Basin can be attributed to long-lived, slab-driven negative dynamic topography. Similarly, for the Arctic, an evolving trend of subsidence from at least the Mid Jurassic to Early Cenozoic, followed by uplift or slowed subsidence to present-day is modelled. This signal is shown to partly account for vertical motions observed at the Barents Sea, Alaska and ...
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