It has been suggested that post-orogenic lithospheric removal in continental back arcs promotes extension and surface subsidence. However, the surface response of this process and its primary difference from “classical” back-arc opening have remained uncertain. Here, the back-arc extension process with varying continental mantle lithosphere thickness and thermal heterogeneities is studied by us...

[1] We determine the crustal and upper mantle structure of southern South America by inverting regional seismograms recorded by the Seismic Experiment in Patagonia and Antarctica. We present a waveform inversion method that utilizes a niching genetic algorithm. The niching genetic algorithm differs from the traditional genetic algorithm in that the inversion is performed in multiple subpopulati...

The long-term stress-state of the lithosphere results from a combination of boundary forces, surface loads and tractions frommantle flow. Here, we have employed a numerical technique which allows for the selfconsistent treatment of the interaction between the lithosphere and mantle and takes into account the deformation of the free-surface. We have used this to study lithospheric dynamics in or...

Seismicity along continental transform faults is usually confined to the upper half of the crust, but the Newport-Inglewood fault (NIF), a major fault traversing the Los Angeles basin, is seismically active down to the upper mantle. We use seismic array analysis to illuminate the seismogenic root of the NIF beneath Long Beach, California, and identify seismicity in an actively deforming localiz...

We propose a mechanism previously developed as a hypothetical cause of the initiation of subduction in the Earth's mantle, to describe a situation where such subduction may occur transiently, at irregular intervals of time. It has been suggested that tectonics on Venus may be described by such a scenario. In our model, a subduction event is followed by resumption of high Rayleigh number mantle ...

Ocean basins are formed when continents are broken apart. Adiabatic melt generation that is driven by rifting of continental lithosphere is strongly dependent on the rate of extension. Slow extension results in conductive heat loss from the upwelling mantle, whereas cooling is limited during fast extension and can result in the geotherm intersecting the peridotite solidus. However, there are fe...

[1] A series of steps in the lithospheric thickness of eastern Australia are revealed by the latest seismic surface wave tomographic model and calculations of the horizontal gradient of shear wave speed. The new images incorporate data from the recent Tasmal experiment, improving resolution in continental Australia. Through comparisons with surface geology and geochemical studies, it is possibl...