Carbonatites and related mineralization: an overview

Abstract

Despite of their scarcity, carbonatites are documented from diverse geological settings, including cratons, continental rifts, orogenic belts and large igneous provinces, which range in age from the Archean to Recent. This study provides a concise overview of the evolution of igneous carbonatites, compiling data on their diverse characteristics and classifying them into mantle- and crustal-derived subtypes. Mantle-derived carbonatites, typically associated with alkaline rocks, are enriched in rare earth elements (REEs) and display geochemical affinities to the mantle. By contrast, crustal-derived carbonatites usually show much lower REE contents and crustal-affinity geochemical features similar to sedimentary carbonaceous rocks. Our study documents the significant economic potential of carbonatites that can host world-class deposits of REE, rare metals, alkaline earth metals and non-metallic resources. Typically, the key processes controlling REE mineralization include the low-degree melting of refertilized mantle, liquid immiscibility, fractional crystallization and hydrothermal fluids. Thus, carbonatites are of significant economic value due to the rapidly increasing global demand for REEs, mainly driven by the ‘green energy transition’.