A stochastic approach to seismic inversion using the ensemble Kalman filter (EnKF) is proposed. Seismic depth and time image data are used as the input for EnKF stochastic seismic inversion. The sonic log is used to estimate source wavelet and create initial models for the inversion, which provides an efficient integration of sonic log data and seismic data. We use both travel time and waveform...

This Nemorandum describes an investiga%ion into the flow fluctuations occurring in two mismatched otaiges in the N.G.T.E. 106 low speed CCmpre3s0r. It3 pur~~ose is to contribute tn a gener,ll understanding of surgin,-, and unstea:iy flow-phenomena in Pull scale compressors when operating in a mismatched condition. licit wire anemometers were used to ex:lmine the fluctuations, measurements being...

The motion of an edge dislocation is analyzed for temperatures ranging from 10 K to 200 K and for stresses up to 5 GPa. The dislocation velocity versus the applied shear stress curve can be divided into four regimes corresponding to successively higher shear stresses. In the first regime, the applied shear stress is below the Peierls stress and the dislocation velocity is nominally zero. In the...

The study of the fluid dynamics of violent volcanic eruptions by laboratory experiment is described, and the important fluid-dynamic processes that can be examined in laboratory models are discussed in detail. In prelim•inary experiments, pure gases are erupted from small reservoirs. The gases used are Freon 12 and Freon 22, two gases of high molecular weight and high density that are good anal...

<p style='text-indent:20px;'>This paper focuses on two-dimensional continuous subsonic-sonic potential flows in a semi-infinitely long nozzle with straight lower wall and an upper which is convergent at the outlet while far fields. It proved that if variation rate of cross section suitably small, there exists unique such sonic curve intersects fixed point velocity flow along normal direct...

<p style="text-indent:20px;">This paper concerns continuous subsonic-sonic potential flows in a two dimensional convergent nozzle, which is governed by free boundary problem of quasilinear degenerate elliptic equation. It shown that for given nozzle perturbation an straight one, and mass flux, there exists uniquely flow whose velocity vector along the normal direction at inlet sonic curve...

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...