Block II: Computational options

Similarly to the other modules, the output is controlled by a number of one-letter options:

C

Produces a contour plot of the spatial spectrum of the surface generated ambient noise vs. frequency and horizontal slowness. This option overrides option K.

F

Produces a curve plot of the noise level in dB vs frequency for each sensor in the receiving array.

J

Applies a complex integration contour with offset given in Block III for all wavenumber integrations.

K

Creates a plot of the wavenumber spectrum of the surface generated ambient noise for each individual frequency.

N

Outputs the noise covariance matrices to a direct access file with extension .xsm . The file format is described below.

P

Produces plots of noise intensity vs. receiver number for each selected frequency.

R

Outputs the array replicas to a file with extension .rpo . The file format is described below.

T

Produces a transfer function file with extension .trf for the selected array and one discrete source. Only allowed for NDNS = 1 . For file format see OASP . The ranges for the receivers in the .trf file are not the true ones, but simply the receiver numbers. To plot all traces together use range stacking in PP .

Z

Produces a plot of the sound speed profiles in the standard format.

b

Solves the depth-separated wave equation with the lowermost interface condition expressed in terms of a complex reflection coefficient. The reflection coefficient must be tabulated in a input file input.trc which may either be produced from experimental data or by the reflection coefficient module OASR as described on Page. See also there for the file format. The lower halfspace must be specified as vacuum and the last layer as an isovelocity fluid without sources for this option. Add dummy layer if necessary. Further, the frequency sampling must be consistent. Using OASR this is optained by using the same minimum and maximum frequencies, and number of frequencies, but without option C . Note: Care should be taken using this option with a complex integration contour, option J . The tabulated reflection coefficient must clearly correspond to the same imaginary wavenumber components for OASN to yield proper results. OASR calculates the reflection coefficient for real horizontal wavenumbers.

t

Solves the depth-separated wave equation with the top interface condition expressed in terms of a complex reflection coefficient. The reflection coefficient must be tabulated in a input file input.trc which may either be produced from experimental data or by the reflection coefficient module OASR as described on Page. See also there for the file format. The upper halfspace must be specified as vacuum and the first layer as an isovelocity fluid without sources for this option. Add dummy layer if necessary. Further, the frequency sampling must be consistent. Using OASR this is optained by using the same minimum and maximum frequencies, and number of frequencies, but without option C . Note: Care should be taken using this option with a complex integration contour, option J . The tabulated reflection coefficient must clearly correspond to the same imaginary wavenumber components for OASN to yield proper results. OASR calculates the reflection coefficient for real horizontal wavenumbers.

#

A digit (1-9) identifying the order of the surface source correllation. The default is totally uncorrelated sources. Higher numbers yield more vertical directionality.