ISBN-13: 9783639099140 / Angielski / Miękka / 2009 / 200 str.
ISBN-13: 9783639099140 / Angielski / Miękka / 2009 / 200 str.
The anatomy of shale is complicated because lithological heterogeneities are present at a very wide range of scales. Both the mineral and pore space contributions to the net seismic anisotropy of a shale are still subjects for research because of the extreme range of scales involved. This research develops a quantitative approach to understanding the seismic anisotropy of shale caused by the alignment of clay minerals and pores. In other words, it answers the questions like when do the clay platelets dominate the anisotropy and when does the porosity play a role? This question is of interest for exploration purposes because the presence of cracks enhances the permeability. The answer depends upon the saturation of the pores - water-filled vs. gas-filled. The theoretical understanding of the effective media modeling is used to model Barnett Shale, which is one of the largest natural gas plays in the World. Upscaling method based on pair correlation function approximation, Backus, and simple averaging are compared for more accurate upscaling estimate of velocities at surface seismic exploration scales.