Figure 4. S-wave velocity VS shown as a function of the volumetric fraction of hydrate (Cgh) in deepwater sediment for each of the four hydrate-sediment models illustrated in Figure 2. Layer Models C and D allow both a slow mode (dashed curve) and a fast mode (solid curve) to propagate. Sediment porosity is defined to be 0.37, and effective pressure is assumed to be 0.01 MPa.