Lamproite and Kimberlite of the Sayany Area: Composition, Sources, and Diamond Potential

摘要

The southwestern part of the Siberian Platform (Eastern Sayany area) is a promising region for discovery of placer and original diamond deposits of various genetic types [ 1, 2]. Several stages of lamproite and kimberlite intrusion are distinguished within the Eastern Sayany area: Mesoproterozoic (Middle Riphean, ～1200 Ma), Neoproterozoic (Vendian, ～630 Ma), and Middle Paleozoic (Devonian, ～370 Ma) (Fig. 1). The highest activity of potassic ultrabasic and alkaline magmatism was registered in the Vendian and was reflected in the formation of dyke bodies and diatremes of mica picrite, alnoite, olivine melilitite, limburgite, and damkjernite synchronously with kimberlite.