Superbursts are thought to be powered by the unstable ignition of a carbon-enriched layer formed from the burning of accreted hydrogen and helium. As shown by Cumming & Bildsten, the short recurrence time hinges on the crust being sufficiently hot at densities ρ > 109 gcm−3. In this Letter, we self-consistently solve for the flux coming from the deep crust and core. The temperature where the ca...

[1] ODP Legs 129 and 185 sampled the upper 474 m of 170 Ma ocean crust in the western Pacific in order to investigate alteration processes in fast spread crust and to determine inputs to subduction. Fourteen composite bulk samples of altered upper oceanic crust from Site 801 have dO = 8.7–25.7%, dD = 69.4% to 90.4%, and dC = 2.7% to 1.8%. The intensity of alteration and the amount of sediment w...

The structure of the crust and uppermost mantle beneath Iceland, the keys to understanding the magma plumbing system of the hotspot and hotspot–ridge interaction, was poorly constrained in previous seismological investigations. Here we develop a three-dimensional P-wave velocity model of the Icelandic crust and uppermost mantle from tomographic inversion of over 3500 first-arrivals from local e...

The size of the Mercurian core and the low ferrous iron bearing silicate content of its crust offer constraints on formation models for the planet. Here we consider a bulk composition that allows endogenous formation of the planet's large core, and by processing the mantle through a magma ocean, would produce a low-iron crust. More Earth-like bulk compositions require silicate removal, perhaps ...

Nonradial oscillations of relativistic neutron stars with a solid crust are computed in the relativistic Cowling approximation, in which all metric perturbations are ignored. For the modal analysis, we employ three-component relativistic neutron star models with a solid crust, a fluid core, and a fluid ocean. As a measure for the relativistic effects on the oscillation modes, we calculate the r...

We present calculations of magnetic field evolution by the Hall effect and Ohmic decay in the crust of neutron stars (NSs). In accreting NSs, Ohmic decay is always the dominant effect due to the large resistivity. In isolated NSs with relatively pure crusts, the Hall effect dominates Ohmic decay after a time tswitch ≃ 104 yr B−3 12, where B12 is the magnetic field strength in units of 1012 G. W...

The distinctive rift patterns observed on newly formed lava lakes are very likely a product of interaction between heat transfer (cooling of lava) and deformation of the solid crust in response to applied stresses. One common pattern consists of symmetric “zigzag” rifts separating spreading plates. Zigzags can be characterized by two measurable parameters: an amplitude A, and an angle θ between...

Sonobuoys provide an alternative to using long streamers while conducting multi-channel seismic (MCS) studies, in order to provide deeper velocity control. We present analysis and modeling techniques for interpreting the sonobuoy data and illustrate the method with ten overlapping sonobuoys collected in the Ross Sea, offshore from Antarctica. We demonstrate the importance of using the MCS data ...

Understanding the controls for magma ascent and storage depth is important for volcanic hazard assessment. Regional differences in the depths of magma storage between volcanic arcs suggest that the settings of subduction zones and of overriding plates influence howmagma ascends through the crust. Here we use a compilation of data for 70 volcanoes in 15 volcanic regions to better understand the ...

Kimberlites from West Greenland have Hf–Nd isotope as well as major and trace element compositions that are similar to other Group I kimberlites, but that are distinctive in the spectrum of magmas sampled at Earth’s surface. The West Greenland kimberlites have eNdi that ranges from +1.6 to +3.1 and eHfi that ranges from 4.3 to +4.9. The samples exhibit ubiquitous negative DeHfi (deviation from ...