Organic carbon fluxes and ecological recovery from the Cretaceous-Tertiary mass extinction

Differences between the carbon isotopic values of carbonates secreted by planktic and benthic organisms did not recover to stable preextinction Levels for more than 3 million years after the Cretaceous-Tertiary mass extinction. These decreased differences may have resulted from a smaller proportion of marine biological production sinking to deep water in the postextinction ocean. Under this hypothesis, marine production may have recovered shortly after the mass extinction, but the structure of the open-ocean ecosystem did not fully recover for more than 3 million years.