Highly abundant and rich in Mg (R₀₀₂=2.46), ultramfic serpentinites of the Great Serpentite Belt, New South Wales (NSW), Australia, represent one of the best potential feedstocks for ex-situ mineral sequestration. Mineral sequestration mimics natural, exothermic weathering reactions that transform Mg- or Ca-rich silicates into thermodynamically stable carbonates, promising to be an important factor in the sequestration of anthropogenic CO₂ emissions. The Attunga magnesite deposit, near Tamworth, NSW, formed through carbonation of ultramafic serpentinite rocks at shallow crustal levels and represents a natural analogue to mineral carbonation. Study of natural analogues complements experimental studies and assists in the advancement of economically viable and energy efficient processes for large scale industrial implementation of mineral sequestration. Rock textures suggest that carbonation was the result of dissolution/re-precipitation processes by low temperature, meteoric-derived fluids under near-surface pressure conditions. The alteration of serpentinised olivine mesh cells is identified as the primary mechanism of progressive magnesite vein formation in the early stages of carbonation and the inferred crystallisation sequence is used to interpret fluid evolution.
Third International Conference on Accelerated Carbonation for Environmental and Materials Engineering (ACEME 10). Proceedings of the Third International Conference on Accelerated Carbonation for Environmental and Materials Engineering (ACEME 10) (Turku, Finland 29 November - 1 December, 2010) p. 121-130