As we moved upslope during the first dive of the 2021 North Atlantic Stepping Stones expedition, we saw many scenes like this one, where a diversity of corals and sponges covered exposed rock surfaces. These live corals and sponges were frequently seen in conjunction with dead coral and sponge stalks that were covered in a ferromanganese coating. Scientists estimate this coating grows at a rate of approximately one millimeter every million years, suggesting that the corals and sponges had been dead for quite some time.
Live Community Near Ferromanganese Coating
Image courtesy of NOAA Ocean Exploration, 2021 North Atlantic Stepping Stones: New England and Corner Rise Seamounts. Download larger version (jpg, 1.2 MB).

As we moved upslope during the first dive of the 2021 North Atlantic Stepping Stones expedition, we saw many scenes like this one, where a diversity of corals and sponges covered exposed rock surfaces. These live corals and sponges were frequently seen in conjunction with dead coral and sponge stalks that were covered in a ferromanganese coating. Scientists estimate this coating grows at a rate of approximately one millimeter every million years, suggesting that the corals and sponges had been dead for quite some time.

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