Yellow iron oxide comes from hydrothermal vents; white is bacterial mat.

Image ID: nur05019, Voyage To Inner Space - Exploring the Seas With NOAA Collect
Location: Hawaii, Pele's Vents
Photo Date: 1988 July
Photographer: A. Malahoff
Credit: OAR/National Undersea Research Program (NURP); Univ. of Hawaii - Manoa

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