Fragmentation of continental subduction is ending the Himalayan orogeny.

After two continents collide, plate convergence and orogenesis are sustained because subducted continental lithosphere continues pulling the surface plate. It remains controversial how, why, and when continental plate convergence and collision slow down and eventually cease. We use an unprecedented data coverage and present a regional-scale seismic tomographic image of the mantle structure beneath the Tibetan Plateau.

Kinematics and dynamics of the East Pacific Rise linked to a stable, deep-mantle upwelling.

Earth's tectonic plates are generally considered to be driven largely by negative buoyancy associated with subduction of oceanic lithosphere. In this context, mid-ocean ridges (MORs) are passive plate boundaries whose divergence accommodates flow driven by subduction of oceanic slabs at trenches. We show that over the past 80 million years (My), the East Pacific Rise (EPR), Earth's dominant MOR, has been characterized by limited ridge-perpendicular migration and persistent, asymmetric ridge accretion that are anomalous relative to other MORs.

Dynamic topography change of the eastern United States since 3 million years ago.

Sedimentary rocks from Virginia through Florida record marine flooding during the mid-Pliocene. Several wave-cut scarps that at the time of deposition would have been horizontal are now draped over a warped surface with a maximum variation of 60 meters. We modeled dynamic topography by using mantle convection simulations that predict the amplitude and broad spatial distribution of this distortion.

Low-velocity zone atop the 410-km seismic discontinuity in the northwestern United States.

The seismic discontinuity at 410 km depth in the Earth's mantle is generally attributed to the phase transition of (Mg,Fe)2SiO4 (refs 1, 2) from the olivine to wadsleyite structure. Variation in the depth of this discontinuity is often taken as a proxy for mantle temperature owing to its response to thermal perturbations. For example, a cold anomaly would elevate the 410-km discontinuity, because of its positive Clapeyron slope, whereas a warm anomaly would depress the discontinuity.