A review on geochemical carbon dioxide removal potential of mafic and ultramafic rocks in India

[Geoengineering News]

https://www.sciencedirect.com/science/article/abs/pii/S0012825226000309

Authors: Shreya Katre, K. Ravi, Archana M. Nair

https://doi.org/10.1016/j.earscirev.2026.105419

05 February 2026

Abstract

Scalable geochemical Carbon Dioxide Removal (CDR) technologies are essential for limiting global warming to 1.5 °C. These technologies capture and permanently store atmospheric CO₂ as carbonates using alkaline substrates such as mafic and ultramafic rocks rich in calcium (Ca) and magnesium (Mg) minerals. This study is the first to comprehensively map and assess the significant geological resources of India for geochemical CDR. Ophiolitic sequences, mafic dyke swarms in cratons, and basaltic formations contain diverse Ca- and Mg-rich silicate minerals, providing substantial alkalinity sources for effective CO₂ sequestration through aqueous engineered carbon mineralisation and enhanced chemical weathering. Analysis of 500 data points across India revealed an average CDR potential of ∼424 gCO₂/kg through alkalinity production and ∼270 gCO₂/kg via carbonation. Ultramafic rocks, including dunite, harzburgite, and peridotite, demonstrated the highest average CDR potential (∼647 gCO₂/kg), while mafic rocks, such as gabbro and basalt, showed moderate potential (∼308 gCO₂/kg). A shrinking core model assessed how rock composition affects cumulative CDR potential over 0–70 years under ambient conditions. Dunite showed the highest sCDR potential (∼441 gCO₂/kg), followed by peridotite (∼298 gCO₂/kg), while plagioclase-rich rocks like gabbro exhibited much lower rates (<30 gCO₂/kg). These results underline the high CDR efficiency of ultramafic rocks and highlight olivine-rich rocks as promising candidates for rapid CO₂ mineralisation, achieving substantial sequestration on human timescales. In summary, this study highlights the vast potential of India's geological resources for CDR through geochemical pathways.

Source: ScienceDirect