Carbonate Precipitation in Artificial Soils Produced from Basaltic Quarry Fines and Composts: An Opportunity for Passive Carbon Sequestration

D.A.C. Manning, P. Renforth, E. Lopez-Capel, S. Robertson, N. Ghazireh Abstract The proportions of different carbon pools within artificial soils prepared by blending composts with dolerite and basalt quarry fines has changed over a period of 7 years, accumulating inorganic carbon as carbonate minerals newly formed within the soils. With no artificial energy inputs following construction, this is regarded as a passive mineral carbonation process. Carbon isotope data show that up to 40% of the carbon within the soil carbonate is derived from photosynthesis, mixed with carbon from geological sources (limestone present in the quarry fines). ...