• S-wave velocity gradients with depth and absolute velocities in the Alaskan crust mantle. Thin upper plate lithosphere low asthenospheric reflect subduction effects. Thick high northern Alaska, part due to original tectonic terranes. The present-day lithospheric structure of Alaska is result a unique history terrane accretion that controls thickness rheology. To provide new constraints on man...

The northern Main Ethiopian Rift (MER) in East Africa is considered a region of incipient oceanic spreading, with Miocene border faulting now largely abandoned at the expense magmatic extension Wonji Fault Belt (WFB). However, whether began when lithosphere was still-thick, or heavily stretched, unknown. Galema range, linear Pliocene dike swarm parallel to eastern margin present-day central MER...

A simple model for the development and evolution of sedimentary basins is proposed. The first event consists of a rapid stretching of continental lithosphere, which produces thinning and passive upwelling of hot asthenosphere. This stage is associated with block faulting and subsidence. The lithosphere then thickens by heat conduction to the surface, and further slow subsidence occurs which is ...

S U M M A R Y Many unresolved questions in geodynamics revolve around the physical behaviour of the two-phase system of a silicate melt percolating through and interacting with a tectonically deforming host rock. Well-accepted equations exist to describe the physics of such systems and several previous studies have successfully implemented various forms of these equations in numerical models. T...

[1] On the basis of the use of broadband (25–150 s) Rayleigh wave group speeds to estimate the 2y component of azimuthal anisotropy, we present evidence for a stratification of anisotropy in the uppermost mantle at large scales across the Pacific basin. We confirm previous surface wave studies that established that the fast axis directions of azimuthal anisotropy for intermediateand long-period...