Non-linear traveltime inversion for 3-D seismic tomography in strongly anisotropic media

Seismic Traveltime Tomography 1

Upwind Nite Diierence Traveltime for Anisotropic Media

The rst arrival quasi-P wave traveltime eld in an anisotropic elastic solid solves a rst order nonlinear partial diierential equation, the qP eikonal equation. Since the qP slowness surface is convex, the rst arrival traveltime along downward propagating rays solves the paraxial qP eikonal equation, an evolution equation in depth. A second order upwind nite diierence scheme solves this paraxial...

Irregular interface parametrization in 3-D wide-angle seismic traveltime tomography

S U M M A R Y We investigate the potential advantages and pitfalls of using an irregular interface parametrization in 3-D wide-angle seismic traveltime tomography. Several synthetic tests are performed using an interface surface consisting of a mosaic of cubic B-spline surface patches and a source–receiver array designed to produce a highly variable distribution of refracted and reflected ray p...

Temporal Integration Of Seismic Traveltime Tomography

Time-lapse geophysical measurements and seismic imaging methods in particular are powerful techniques for monitoring changes in reservoir properties. Traditional time-lapse processing methods treat each dataset as an independent unit and estimate changes in reservoir state through differencing these separate inversions. We present a general least-squares approach to jointly inverting time-varyi...

Applying Compactness Constraints To Seismic Traveltime Tomography

Tomographic imaging problems are typically ill-posed and often require the use of regularization techniques to guarantee a stable solution. Minimization of a weighted norm of model length is one commonly used secondary constraint. Tikhonov methods exploit low-order differential operators to select for solutions that are small, flat, or smooth in one or more dimensions. This class of regularizin...