We perform two-dimensional simulations of Alfvén oscillations in magnetars, modeled as relativistic stars with a dipolar magnetic field. We use the anelastic approximation to general relativistic magnetohydrodynamics, which allows for an effective suppression of fluid modes and an accurate description of Alfvén waves. In addition, we compute Alfvén oscillation frequencies along individual magne...

This study focuses on measurements of clastic rocks ranging from 3 Hz up to 500 kHz in the laboratory and their application to well log analysis and a time-lapse study in the North Sea. Measurements of elastic properties over a large frequency spectrum can provide a better understanding of the dispersion and attenuation mechanisms in rocks and help to predict and model these effects. Sandstones...

Summary The elastic and anelastic structures of the Earth offer fundamental constraints for understanding its physical chemical properties. Deciphering small variations in velocity amplitude seismic waves can be challenging. Advanced approaches such as full-waveform inversion (FWI) useful. We re-write Fréchet kernel expression Fichtner & van Driel (2014) using displacement-stress formulatio...

[1] The anelastic response of single-crystal and polycrystalline quartz and quartz-rich sandstones to applied stress at low frequencies has been investigated by dynamic mechanical analysis and force torsion pendulum measurements. The dynamic modulus was measured on heating and cooling through the a-b phase transition under shear and bending stress applied at low frequency (~1Hz). Single crystal...

A conceptual model is proposed for the generation of low-angle normal faults in Metamorphic Core Complexes. The model is based on three assumptions: (1) the isostatic response to normal fault motion is of regional extent; (2) when a fault segment is significantly rotated from the optimum angle of slip, relative to the crustal stress field, it is replaced by a new planar fault oriented in the op...