Prognostication of primary diamond deposits

Prognostication of primary diamond deposits (kimberlites and lamproites), located within diamondiferous provinces on ancient cratons, is based on using geological, geophysical and morphostructural models for kimberlite/lamproite zones, fields and clusters. The zones that control kimberlite/lamproite emplacement are characterised by widespread development of intrusive and volcanic rocks and block structure. They are reflected in geophysical data by sharply contrasting, elongated magnetic and gravity anomalies. The zones are divided into transcurrent intracratonic, rift-related and zones of anomalous mantle. Within these broader zones kimberlite/lamproite fields are characterised by dome/block-shaped uplifts in geological structures; by subcircular seismic, gravity and magnetic anomalies, and by concentric-radial morphological structures. They may be recognised by the integrated analysis of geological, geophysical and topographical maps, as well as aerial and satellite images. Several new kimberlite fields have been found using these techniques.