About 93 million years ago, a burst of volcanic activity on the ocean floor led to a massive extinction event that killed one-tenth of the world's marine invertebrates, according to a new study. The Caribbean region was the likely source of the sea-floor eruptions, says [study coauthor Steven]
Turgeon. He says massive amounts of lava would have burbled and blasted up from inside the earth, setting off a "chain reaction" that took thousands of years to play out [Canwest News Service].
[T]he volcanoes spewed out metal-rich fluids that seeded the upper level of the ocean with micronutrients.... Tiny life forms on the sea surface, called phytoplankton, gorged on the food, and storing up carbon as they grew. They then sank to the sea floor and decayed, stripping the ocean of oxygen [BBC News]
Researchers had long known that a loss of oxygen in the world's oceans occurred during the Cretaceous ...
