Understanding how elastic waves propagate in complicated structures will require elastic wave modeling with realistic structural models. Computational requirements for elastic model calculations may be 100 to 200 times greater than for an equivalent acoustic problem. The industry liaison is Fred Aminzadeh, Unocal. These data sets were collected to compare 3-D imaging results from the two very different acquisition methods, as well as from the acoustic numerical data set. Data collected using vertical receiver cables are truly 3-D, since they cover a large range of azimuths.
Materials are available that do support shear wave propagation.
We will investigate if it is feasible to construct a new model that supports shear waves and collect physical model data to augment and compare to the elastic model data. The industry liaison is Robert Wiley, Marathon. This task is developing methods for faster and more reliable 3-D velocity estimation, and for solving inverse and rock property estimation problems. Development of new methods for solving large inverse problems and for seismic data synthesis and data fusion has been applied to problems of determining residual statics and estimating and extrapolating rock properties from seismic data. The methods provide excellent or optimal solutions, yet the problems can be so large, and the solution methods so complex, that physical intuition alone is not a reliable guide to estimating the uncertainty in the solutions.