fzmodeler

Bash script to build fracture zone cross-profile model

Synopsis

fzmodeler [ -Aasymmetry ] [ -Ccompression ] [ -Dmin/max/inc ] [ -Gcomp ] [ -M ] [ -Namplitude ] [ -O ] [ -P ] [ -Sshift ] [ -Tprefix ] [ -V[level] ] [ -Wwidth ]

Note: No space is allowed between the option flag and the associated arguments.

Description

zmodeler is a script developed as part of the Global Seafloor Fabric and Magnetic Lineation Project [see GSFML for a full description of the project]. It builds a synthetic model cross-profile given the chosen model parameters and optionally images the profile via a PDF plot. The model evaluated is $$z(x) = A[mG_1 + (1-m)(uG_2 - G_0)]$$, where A is amplitude (-N), m is asymmetry (-A), and u is compression (-C). Here $$G_0$$ is the Gaussian function, while $$G_1$$ and $$G_2$$ are the first two horizontal derivatives. Note: The blend model subtracts Here $$G_0$$ since for fracture zones we want the negative Gaussian.

Optional Arguments

-Aasymmetry

Sets the asymmetry parameter used for the blend between symmetric (“Atlantic”) and asymmetric (“Pacific”) signals [0].

-Ccompression

Sets the amount of compression (0-1) to use in the blending [0].

-Dmin/max/inc

Sets the domain for which to evaluate the model. If -M is used then the domain is expected to be in km; otherwise min and max will be expected to be in degrees of latitude which inc will be decoded as arc minutes [-5/5/2 or -100/100/2, depending on -M].

-Gcomp

Only plot component $$G_i(x)$$, where i = 0, 1, or 2

-M

The chosen domain (-D) is given degrees of latitude, with increment in arc minutes [Default is in km].

-Namplitude

Sets the peak-to-trough amplitude of the blended signal [100].

-O

Instead of making a stand-alone PDF plot, write a PostScript overlay to stdout, i.e., make the plot using the GMT classic code -O -K options. Requires (or sets) -P.

-P

Produce a PDF plot (named prefix.pdf) of the synthetic FZ profile [no plot].

-Sshift

Sets the shift of the FZ location from the origin, in km [0].

-Tprefix

Set the output prefix for the model profile [fzprof]. Give -T- to send the model profile to stdout.

-V[level]

Select verbosity level [w]. (See full description) (See cookbook information).

-Wwidth

Sets the full width of the FZ, in km [25].

Examples

To plot a synthetic profile for the Pacific, using otherwise default arguments, try:

fzmodeler -C1 -V


The final plot will be named prefix.pdf, with the model data in prefix.txt. To just plot normalized component $$G_2(x)$$, try:

fzmodeler -D-30/30/1 -C1 -N1 -W10 -G2 -T- | gmt plot -W1p -B -R-30/30/-1/1 -png G2