A selection of blues which may be useful for bathymetric maps.
blue
blues
Blues 09
crisp ice
cyanotype 01
cyanotype 02
Deep Sea
GnBu 09
jeans
occ019
occ079
pastel purple blue
PuBu 09
purplish blue
rain
sky blue
twilight
YlGnBu 09
See also: Skywalker, Sea Dreams.