The Gaussian wavelet is widely used as a shaping wavelet for scattered wave imaging with P receiver functions due to widespread use of the iterative deconvolution method. We show the Gaussian wavelet degrades the resolution of plane wave migration by comparing results from the latest USArray data shaped with Gaussian and Ricker wavelets. We use simulations of primary conversions from the 410 a…

The attenuation and velocity dispersion of sonic waves contain valuable information on the mechanical and hydraulic properties of the probed medium. An inherent complication arising in the interpretation of corresponding measurements is, however, that there are multiple physical mechanisms contributing to the energy dissipation and that the relative importance of the various contributions is di…

Hydrocarbon reservoir pressure depletion leads to stress changes inside the reservoir and ground deformation which is registered at the surface as subsidence. As reservoirs are often overlain by layers of rocksalt (or other evaporites), which are materials that flow so as to relax stresses inside them, there is the potential for time-varying surface subsidence. This work focuses on understandin…

Heterogeneous velocity structures are expected to affect fault rupture dynamics. To quantitatively evaluate some of these effects, we examine a model of dynamic rupture on a frictional fault embedded in an elastic full space, governed by plane strain elasticity, with a pair of off-fault inclusions that have a lower rigidity than the background medium.We solve the elastodynamic problem using the…

On 2012 September 5, the anticipated interplate thrust earthquake ruptured beneath the Nicoya peninsula in northwestern Costa Rica close to the Middle America trench, with a magnitude Mw 7.6. Extensive co-seismic observations were provided by dense near-field strong ground motion, Global Positioning Systems (GPS) networks and teleseismic recordings from global seismic networks. The wealthy data…

We present a new Sv-velocity model of the upper mantle under East and Southeast Asia constrained by the inversion of seismic waveforms recorded by broad-band stations. Seismograms from earthquakes occurred between 1977 and 2012 are collected from about 4786 permanent and temporary stations in the region whenever and wherever available. Automated Multimode Inversion of surface and multiple-S wav…

We present a new technique for modelling the global lithospheric magnetic field at Earth’s surface based on the estimation of equivalent potential field sources. As a demonstration we show an application to magnetic field measurements made by the CHAMP satellite during the period 2009–2010 when it was at its lowest altitude and solar activity was quiet. All three components of the vector fi…

Archaeological baked clay remains provide valuable information about the geomagnetic field in historical past, but determination of the geomagnetic field characteristics, especially intensity, is often a difficult task. This study was undertaken to elucidate the reasons for unsuccessful intensity determination experiments obtained from two different Bulgarian archaeological sites (Nessebar – …

Data assimilation is a technique that optimizes the parameters used in a numerical model with a constraint of model dynamics achieving the better fit to observations. Optimized parameters can be utilized for the subsequent prediction with a numerical model and predicted physical variables are presumably closer to observations that will be available in the future, at least, comparing to those ob…

Ongoing works on full waveform inversion (FWI) are yielding an increasing number of objective functions as alternative to the traditional L2-waveform. These studies aim at designing more robust functions and inversion strategies to reduce the intrinsic dependence of the FWI results on (1) the initial model and (2) the lowest frequency present in field data. In this work, we perform a comparativ…