Figure F25. A. Hole 1177A P-wave velocity. B. Horizontal and vertical P-wave velocity as a function of porosity. The line represents a typical relationship for clayey silt computed from a weighted average equation (Lee et al., 1996). Units I, II, III, IV, and V refer to the lithostratigraphic units. C. P-wave anisotropy. The vertical plane anisotropy compares velocity along the two transverse axes (x and y) to that parallel to the core (z), whereas the horizontal plane anisotropy compares velocity of the x- and y-axes. Because cores are randomly rotated, horizontal plane anisotropy should average zero.