Open AccessMechanistic Links Between the Sedimentary Redox Cycle and Marine Acid‐Base Chemistry
Author(s) -
Reinhard Christopher T.,
Fischer Woodward W.
Publication year - 2019
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2019gc008621
Subject(s) - hydrosphere , sedimentary rock , earth science , geology , precambrian , carbonate , weathering , carbonate minerals , carbon cycle , sedimentary basin , proterozoic , redox , calcite , geochemistry , ocean chemistry , paleontology , seawater , biosphere , oceanography , tectonics , chemistry , ecology , organic chemistry , ecosystem , biology
The redox state of Earth's surface is controlled on geological timescales by the flow of electrons through the sedimentary rock cycle, mediated largely by the weathering and burial of C‐S‐Fe phases. These processes buffer atmospheric p O 2 . At the same time, CO 2 influxes and carbonate burial control seawater acid‐base chemistry and climate over long timescales via the carbonate‐silicate cycle. However, these two systems are mechanistically linked and impact each other via charge balance in the hydrosphere. Here, we use a low‐order Earth system model to interrogate a subset of these connections, with a focus on changes that occur during perturbations to electron flow through the sedimentary rock cycle. We show that the net oxidation or reduction of the Earth's surface can play an important role in controlling acid‐base processes in the oceans and thus climate, and suggest that these links should be more fully integrated into interpretive frameworks aimed at understanding Earth system evolution throughout Precambrian and Phanerozoic time.