Potential for large igneous province volcanism to drive transient atmospheric deoxygenation in the Paleoproterozoic

The Great Oxidation Event (GOE), the first major rise of the atmospheric oxygen level, occurred at ∼2.4–2.2 billion years ago in the early Paleoproterozoic. Emerging geochemical evidence has raised the possibility of repeated short-term atmospheric oxygen fluctuations near the end of the GOE, although their occurrence remains debated. Here, we utilize theoretical models to test whether the emplacement of large igneous provinces (LIPs) could explain these fluctuations. Our simulations indicate that LIP emplacement is capable of producing transient atmospheric deoxygenation under Paleoproterozoic boundary conditions and that this transient event increases the deposition of Fe hydroxides from the surface ocean. The Paleoproterozoic atmospheric oxygen level can drop sharply to anoxic conditions after LIP emplacement and recover within ∼0.5 million years owing to ocean eutrophication. This phenomenon is particularly favored under Paleoproterozoic boundary conditions, suggesting that LIP volcanism provides a plausible mechanism for the potential transient atmospheric deoxygenation events in the Paleoproterozoic.