Coggon et al. (2025): A geological carbon cycle sink hosted by ocean crust talus breccias

Rosalind M. Coggon, Elliot J. Carter, Lewis J. C. Grant, Aled D. Evans, Christopher M. Lowery, Damon A. H. Teagle, Pamela D. Kempton, Matthew J. Cooper, Claire M. Routledge, Elmar Albers, Justin Estep, Gail L. Christeson, Michelle Harris, Thomas M. Belgrano, Jason B. Sylvan, Julia S. Reece, Emily R. Estes and Trevor Williams on behalf of The South Atlantic Transect IODP Expedition 390 & 393 Scientists, IN: Nature Geoscience, https://doi.org/10.1038/s41561-025-01839-5

Calcium carbonate precipitation in ageing ocean crust sequesters carbon dioxide dissolved in seawater through seafloor weathering reactions, influencing atmospheric CO₂ concentrations on million-year timescales. However, this crustal carbon sink, and the extent it balances CO₂ degassing during crustal formation at mid-ocean ridges, remain poorly quantified due to limited sampling of the vast ridge flanks where CO₂ uptake continues for millions of years. Here the authors quantify the carbon sink hosted within talus breccias that accumulated through mass wasting 61 million years ago during rift faulting at the slow spreading Mid-Atlantic Ridge, cored during International Ocean Discovery Program South Atlantic Transect Expedition 390.

LINK