Seismic surface wave focal spot imaging: numerical resolution experiments

High-resolution surface-wave tomography from ambient seismic noise.

Cross-correlation of 1 month of ambient seismic noise recorded at USArray stations in California yields hundreds of short-period surface-wave group-speed measurements on interstation paths. We used these measurements to construct tomographic images of the principal geological units of California, with low-speed anomalies corresponding to the main sedimentary basins and high-speed anomalies corr...

The effect of focal spot size on the spatial resolution of variable resolution X-ray CT scanner

Background: A variable resolution X-ray (VRX) CT scanner provides a great increase in the spatial resolution. In VRX CT scanners, the spatial resolution of the system and its field of view (FOV) can be changed according to the object size. One of the main factors that limit the spatial resolution of VRX CT scanner is the effect of the X-ray focal spot. Materials and Methods: A theoreti...

Experiments on seismic metamaterials: molding surface waves.

Materials engineered at the micro- and nanometer scales have had a tremendous and lasting impact in photonics and phononics. At much larger scales, natural soils civil engineered at decimeter to meter scales may interact with seismic waves when the global properties of the medium are modified, or alternatively thanks to a seismic metamaterial constituted of a mesh of vertical empty inclusions b...

Modelling Seismic Wave Propagation for Geophysical Imaging

High-resolution lithospheric imaging with seismic interferometry

In recent years, there has been an increase in the deployment of relatively dense arrays of seismic stations. The availability of spatially densely sampled global and regional seismic data has stimulated the adoption of industry-style imaging algorithms applied to convertedand scattered-wave energy from distant earthquakes, leading to relatively high-resolution images of the lower crust and upp...