Color Bars

Seismic Velocity

CUB use a very beautiful seismic velocity color bar.

gmt begin seismic-velocity png,pdf
    gmt colorbar -Cseismic-velocity.cpt -Dx0c/0c+w10c/0.2c+h+e+n -Bxa1
gmt end show

Seismic velocity color bar

Or you can use the built-in cpt color bar in GMT. If you’d like to output the generated color bar to a file, remember to use the argument -H of makecpt (Modern mode only). Meanwhile, the file name cannot be same as the used built-in cpt name (e.g., seis.cpt in this example).

gmt begin gmt_seis png,pdf
    gmt makecpt -Cseis -T-6/6/0.5 -Z -D
    gmt colorbar -Dx0c/0c+w10c/0.2c+h+e+n -Bxa1
gmt end show

GMT seis color bar

There are some more alternative CPTs that may work well for seismic tomography:

• BlueWhiteOrangeRed

• Roma

gmt begin more_seis_cpts png,pdf
    gmt makecpt -CBlueWhiteOrangeRed.cpt -T-6/6 -I -D
    gmt colorbar -Dx0c/0c+w10c/0.2c+h+e+n -Bxa1
    gmt makecpt -Croma.cpt -T-6/6/0.5 -Z -D
    gmt colorbar -Dx0c/-2c+w10c/0.2c+h+e+n -Bxa1
gmt end show

More Seis color bars