Dynamic modeling of tectonic carbon processes: State of the art and conceptual workflow

Abstract

Plate tectonics plays a critical role in modulating atmospheric CO2 concentration on the geological timescale (⩾106 year). A growing consensus on tectonic and Earth’s CO2 history in the Cenozoic and deeper time provides solid restrictions and standards for testing tectonic carbon processes against global measurements. Despite this, modeling the causal relationship between tectonic events and atmospheric CO2 levels remains a challenge. We examine the current state of the global tectonic CO2 research and suggest a conceptual workflow for numerical experiments that integrates plate tectonics and deep carbon dynamics. Future tectonic carbon cycle modeling should include at least four modules: (1) simulation of carbon-carrying processes, such as carbon ingassing and outgassing at the scale of minerals; (2) calculation of CO2 fluxes in tectonic settings like subduction, mantle plume, and plate rifting; (3) reconstruction of carbon cycling within the plates-scale tectonic scenario, particularly involving the processes of supercontinent convergence and dispersion; and (4) comparison with atmospheric CO2 history data and iterations, aiming to find the coincidental link between different tectonic carbon fluxes and climate changes. According to our analysis, the recent advancements in each of the four modules have paved the path for a more general assembly. We envision that the large variety of carbon transportation parameters across more than ten orders of magnitude in both time and space is the primary technical hurdle in simulating tectonic carbon dynamics. We propose a boundary-condition-connected approach for simulating the global carbon cycle to realize carbon exchange between the solid earth and surface spheres.