Data coverage, expressed as path density of Rayleigh wave group velocities, is shown in Figure 1. Coverage is best at intermediate periods, and reduces particularly at very long periods. It is also considerably lower for Love waves than for Rayleigh waves, especially at periods above about 100 sec. Resolution estimates are shown in Figure 2. Average resolution across the Paci c is about 600 km ...

Both seismic and electrical properties depend on the mineralogical composition of the rock, porosity, fluid content, and in situ stress state. Previous work on effects of CO2 on seismic velocities is limited. Wang and Nur, 1989, measured both compressional (Pwave) and shear (S-wave) velocities on a number of sandstones saturated with nhexadecane and then flooded with CO2. They made measurements...

We collected continuous seismic data recorded between 2007 and 2010 by 208 broadband stations from the Chinese Provincial Digital Seismic Networks, A Seismic Collaborative Experiment of Northern Tibet, and the Northeastern Tibet Seismic experiment. Cross correlations of vertical component records are computed to extract the Rayleigh wave empirical Green’s functions. Group and phase velocities a...

A preferred orientation of the anisotropic ice crystals influences the viscosity of the ice bulk and the dynamic behaviour of glaciers and ice sheets. Knowledge about the distribution of crystal anisotropy is mainly provided by crystal orientation fabric (COF) data from ice cores. However, the developed anisotropic fabric influences not only the flow behaviour of ice but also the propagation of...

[1] Seismic reflection profiles shot across the Cascadia forearc show that a 5–15 km thick band of reflections, previously interpreted as a lower crustal shear zone above the subducting Juan de Fuca plate, extends into the upper mantle of the North American plate, reaching depths of at least 50 km. In the extreme western corner of the mantle wedge, these reflectors occur in rocks with P wave ve...

We estimate shear-wave velocities in the shallow subsurface throughout Japan by applying seismic interferometry to the data recorded with KiK-net, a strongmotion network in Japan. Each KiK-net station has two receivers; one receiver on the surface and the other in a borehole. By using seismic interferometry, we extract the shear wave that propagates between these two receivers. Applying this me...

S U M M A R Y The main purpose of seismic inversion is the retrieval of seismic velocities and densities in the earth. Inversion of body-wave traveltimes cannot uniquely determine the seismic velocities as a function of depth when a low-velocity layer is present. It is generally assumed that surface waves do not suffer from the same non-uniqueness. The issue is addressed whether it is possible ...

The densities and seismic velocities of rocks are relatively weak functions of temperature, pressure and composition unless these are accompanied by a drastic change in mineralogy. The physical properties of a rock depend on the proportions and compositions of the various phases or minerals-the mineralogy. These, in turn, depend on temperature, pressure and composition. In general, one cannot a...

The adiabatic bulk (K(S)) and shear (G) moduli of mantle materials at high pressure and temperature can be obtained directly by measuring compressional and shear wave velocities in the laboratory with experimental techniques based on physical acoustics. We present the application of the current state-of-the-art experimental techniques by using ultrasonic interferometry in conjunction with synch...