Finite-frequency structural sensitivities of short-period compressional body waves

Emergence of body waves from cross - correlation of short period seismic noise 1

Ambient noise correlation is now widely used in seismology to obtain the surface 6 waves part of the Green's function. More difficult is the extraction of body waves from noise 7 correlations. Using 42 temporary broad-band three components stations located on the 8 northern part of fennoscandian region, we identify high frequency (0.5-2 Hz) body waves 9 emerging from noise correlations for inte...

Emergence of body waves from cross-correlation of short period seismic noise

Fast Compressional Alfven Waves in a Tokamak

Enhancement of cyclotron damping is theoretically evaluated based upon the wave E-field polarization which is modified by the two-ion hybrid resonance. The degree of enhancement and its asymmetry about the plasma center is consistent with experimental observations. The enhancement factor is very large at low plasma densities at which most of the past damping strength measurements have been repo...

Compressional waves guided between parallel fractures

We have performed experiments on the laboratory scale to image seismic wavefronts of compressional waves that are guided between parallel fractures. The wavefronts are detected using water-coupled 1MHz piezoelectric transducers. The stiffness of the fractures is controlled by applying radial stress in a hydraulic stress apparatus that leaves the observation face of the fractured sample open to ...

Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise sources

[1] Among the different types of waves embedded in seismic noise, body waves present appealing properties but are still challenging to extract. Here we first validate recent improvements in numerical modeling of microseismic compressional (P) body waves and then show how this tool allows fast detection and location of their sources. We compute sources at ~0.2 Hz within typical P teleseismic dis...