Block IV: Environmental Model

OASSP supports all the environmental models allowed for SAFARI as well as the ones described above in Section 4.1. The significance of the standard environmental parameters is as follows

NL:

Number of layers, including the upper and lower half-spaces. These should always be included, even in cases where they are vacuum.

D:

Depth in m of upper boundary of layer or halfspace. The reference depth can be choosen arbitrarily, and D() is allowed to be negative. For layer no. 1, i.e. the upper half-space, this parameter is dummy.

CC:

Velocity of compressional waves in m/s. If specified to 0.0, the layer or half-space is vacuum.

CS:

Velocity of shear waves in m/s. If specified to 0.0, the layer or half-space is fluid. If CS()< 0, it is the compressional velocity at bottom of layer, which is treated as fluid with 1/c(z)² linear.

AC:

Attenuation of compressional waves in . If the layer is fluid, and AC() is specified to 0.0, then an imperical water attenuation is used (Skretting & Leroy).

AS:

Attenuation of shear waves in

RO:

Density in g/cm³.

RG:

RMS roughness of interface in m. RG(1) is dummy. If RG<0 it represents the negative of the RMS roughness, and the associated correlation length CL should follow. If RG>0 the correlation length is assumed to be infinite.

CL:

Roughness correlation length in m. If RG and CL are both negative, the interface is assumed to be smooth, but the layer below will contain volume inhomogeneities with vertical and horizontal correlation lengths -RG and -CL, respectively.