Is 3C the Future of Land Seismic? Some Reasons for Optimism.

A key principle for understanding and interpreting seismic images of the subsurface is<br>that seismic waves are sensitive to three bulk rock properties: compressibility, rigidity<br>and density. Recording both P-wave and S-wave modes allows better separation of<br>these three properties. S-wave propagation is sensitive only to rigidity and density,<br>while compressional-wave propagation is sensitive to rigidity, density and<br>compressibility. Therefore, P-waves tend to have a higher sensitivity to fluids in the pore<br>space. On the other hand, open fractures more strongly affect rock rigidity and since Swaves<br>are more sensitive to rigidity changes, they are more suited for fracture<br>characterization. Interpreting both P- and S-wave reflectivity offers the ability to<br>discriminate lithology, porosity, fractures and possibly fluid content. However, a number<br>of barriers historically inhibited the acceptance and growth of multicomponent<br>technology.