Massive release of hydrogen sulfide to the surface ocean and atmosphere during intervals of oceanic anoxia

  title={Massive release of hydrogen sulfide to the surface ocean and atmosphere during intervals of oceanic anoxia},
  author={Lee R. Kump and Alexander A. Pavlov and Michael A. Arthur},
Simple calculations show that if deep-water H2S concentrations increased beyond a critical threshold during oceanic anoxic intervals of Earth history, the chemocline separating sulfidic deep waters from oxygenated surface waters could have risen abruptly to the ocean surface (a chemocline upward excursion). Atmospheric photochemical modeling indicates that resulting fluxes of H 2S to the atmosphere (.2000 times the small modern flux from volcanoes) would likely have led to toxic levels of H 2S… 

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