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Impactites (suevites, tagamites, impact glasses) are widespread in the Popigai impact crater. The continuous cover of suevite overlying allogenic polymict breccia is more than 1,000 m thick in the central part of the crater. Suevites also occur in form of lenses or irregular bodies within the allogenic breccia. Tagamites crop out predominantly in the western sector of the crater. Most occur as sheet-like bodies, up to 600 m thick, overlying allogenic breccia and as small irregular bodies in suevites. Commonly tagamites have a complex inner structure with distinct horizontal zones distinguished mainly by crystallinity and fragment content. Differentiation of impact melt bodies was not observed.

Tagamites and suevites are similar in terms of chemical composition and petrographie characteristics: they correspond to the composition of biotite-garnet gneisses of the crystalline basement. The distribution of Ir and Ni indicates that the impact melt was well homogenized. Concentric zonation in SiO2, MgO, Na2O distribution and the band-like distribution of other components testify to an inherited compositional heterogeneity in target rocks within the melting zone. The content of high-pressure carbon phases in these impactites varies radially and reflects shock transformation of former graphite and radial ejection of melt. Detailed exploration of impactite bodies and their composition point to complex processes in melt-forming and rock-forming petrogenetic systems vis-à-vis the impact process.

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