New velocity data in addition to literature data derived from sonic log, seismic, and laboratory measurements are analyzed for elastic silicate rocks. These data demonstrate simple systematic relationships between compressional and shear wave velocities. For water-saturated elastic silicate rocks, shear wave velocity is approximately linearly related to compressional wave velocity and the compr...

The reduction of six wide-angle reflection profiles shot within the two fault blocks visited by Ocean Drilling Program (ODP) Leg 116 in combination with the ODP sonic logs has produced a velocity-depth structure for this area. The sediment velocity increases from 1.6-1.7 km/s in the near surface to 3.4-3.5 km/s immediately above basement with a velocity gradient of 0.75/s. A depth converted sei...

A systematic fluid theory of nonlinear magnetic island dynamics in conventional low, large aspect-ratio, circular cross-section tokamak plasmas is developed using an extended magnetohydrodynamics model that incorporates diamagnetic flows, ion gyroviscosity, fast parallel electron heat transport, the ion sound wave, the drift wave, and average magnetic field-line curvature. The model excludes th...

Formation elastic properties near a borehole may be altered from their original state due to the stress concentration around the borehole. This could lead to a biased estimation of formation elastic properties measured from sonic logging data. To study the effect of stress concentration around a borehole on sonic logging, we first use an iterative approach, which combines a rock physics model a...

Results of the application of optical flow methods to eyesafe aerosol lidar images leading to dense velocity field estimations are presented. A fluid motion dedicated formulation is employed, taking into account the deforming shapes and changing brightness of flow visualization. The optical flow technique has the advantage of providing a vector at every pixel in the image, hence enabling access...

We study the characteristics of the outflow in disks of Be stars, based on the viscous decretion disk scenario. In this scenario, the matter ejected from the equatorial surface of the star drifts outward because of the effect of viscosity, and forms the disk. For simplicity, we adopt the α-prescription for the viscous stress, and assume the disk to be isothermal. Solving the resulting wind equa...

stress waves contain useful information about the properties of porous materials; they can be recovered through different non-destructive testing methods such as crosswell, vertical seismic profile, borehole logging as well as sonic tests. in all these methods, it is crucial to assess the effects of frequency on wave attributes including velocity and intrinsic attenuation. the dependency of per...

We compute the structure function scaling of the integrated intensity images of two J=1-0 CO maps of Taurus and Perseus. The scaling exponents of the structure functions follow the velocity scaling of super–sonic turbulence, suggesting that turbulence plays an important role in the fragmentation of cold interstellar clouds. The data also allows to verify the validity of the two basic assumption...

The morphology and kinematics of molecular clouds (MCs) are best explained as the consequence of super–sonic turbulence. Super–sonic turbulence fragments MCs into dense sheets, filaments and cores and large low density “voids”, via the action of highly radiative shocks. We refer to this process as turbulent fragmentation. In this work we derive the mass distribution of dense cores due to turbul...