This study investigates near-field ground motion variability due to dynamic rupture models with heterogeneity in the initial shear stress. Ground velocity seismograms are synthesized by convolving the time histories of slip velocity obtained from spontaneous dynamic rupture models with Green’s functions of the medium calculated with a discrete wavenumber / finite element method. Peak ground vel...

Ground motions recorded within sedimentary basins are variable over short distances. One important cause of the variability is that local soil properties are variable at all scales. Regional hazard maps developed for predicting site effects are generally derived from maps of surficial geology; however, recent studies have shown that mapped geologic units do not correlate well with the average s...

Context. Future astrometric missions such as SIM PlanetQuest need very stable reference stars. K giants have large luminosities, which place them at large distances and thus the jitter of their photocenters by companions is relatively small. Therefore K giants would be best suited as references. To confirm this observationally a radial velocity survey is performed to quantify the level of intri...

A method has been developed to monitor the surface velocity field by combining repeated acoustic Doppler current profiler (ADCP) observations and satellite altimetry data. The geostrophic velocity anomaly is calculated from the sea surface height anomaly field estimated from the altimetry data by an optimal interpolation. It has been confirmed that this accurately observes the smoothed velocity...