Towards structural imaging using seismic ambient field correlation artefacts

Ambient seismic wave field

The ambient seismic wave field, also known as ambient noise, is excited by oceanic gravity waves primarily. This can be categorized as seismic hum (1-20 mHz), primary microseisms (0.02-0.1 Hz), and secondary microseisms (0.1-1 Hz). Below 20 mHz, pressure fluctuations of ocean infragravity waves reach the abyssal floor. Topographic coupling between seismic waves and ocean infragravity waves at t...

Earthquake ground motion prediction using the ambient seismic field

[1] The waves generated by faulting represent the primary threat posed by most large earthquakes. The effect of complex geological structures, such as sedimentary basins, on earthquake ground motion is a source of particular concern. We show that it is possible to extract reliable phase and amplitude response that includes the effects of complex structure for the elastodynamic Green’s function ...

Seismic Gradiometry using Ambient Seismic Noise in an Anisotropic Earth

Surface Wave Tomography of China from Ambient Seismic Noise Correlation

We perform ambient noise tomography of China using the data from the China National Seismic Network and surrounding global and regional stations. For most of the station pairs, we retrieve good Rayleigh waveforms from ambient noise correlations using 18-months of continuous data at all distance ranges across the entire region (over 5000 km) and for periods from 70 s down to about 8 s. We obtain...

Cross-correlation imaging of ambient noise sources

S U M M A R Y We develop and apply a novel technique to image ambient seismic noise sources. It is based on measurements of cross-correlation asymmetry defined as the logarithmic energy ratio of the causal and anticausal branches of the cross-correlation function. A possible application of this technique is to account for the distribution of noise sources, a problem which currently poses obstac...