Sea Relief

A relief plaque of a stretch of coast, a bay, an island or a lake, where the water is the subject: the seafloor stepping down in bands of colour from the shore to the deep, the land in one colour above it. Type the place; the seafloor under it is real bathymetry, from the same elevation data as every map here — not a blue fill. The floor is cut into steps at real depths, the shelf, the slope, the abyss, each its own colour. Four depth sets, from a harbour's metres to an ocean's kilometres. The place name along the foot. PLA.