Before revision: In a paper published in 1998 in Nature, Canfield argued that the ocean was anoxic and sulfidic during the time of the Boring Billion , and that those conditions affected the mineral deposition of iron-rich banded iron formations (BIF) .
After revision: In a paper published in 1998 in Nature, Canfield argued that the ocean was anoxic and sulfidic during the time of the Boring Billion , and that those conditions ceaseddeep(also known as euxinic)(1.8 Ga - 0.8 Ga)in ocean sediments the mineral deposition of iron-rich banded iron formations (BIF) .