TY - JOUR

T1 - Diamonds in lavas of the Tolbachik fissure eruption in Kamchatka

AU - Gordeev, E.I.

AU - Karpov, G.A.

AU - Anikin, L.P.

AU - Krivovichev, S.V.

AU - Filatov, S.K.

AU - Antonov, A.V.

AU - Ovsyannikov, A.A.

PY - 2014

Y1 - 2014

N2 - Diamond crystals 0.05-0.2 mm (rarely up to 0.7 mm) in size were found in lavas of the Tolbachik fissure eruption (TFE, Kamchatka, 2012-2013). The TFE basaltic lavas with diamonds in the pores are similar in chemical composition to the lavas of the Great Tolbachik Fissure Eruption (GTFE, Kamchatka, 1975-1976); however, the basalts of the new eruption contain slightly more SiO2 and higher Fe relative to those of GTFE. Basalts of both eruptions are close in trace element composition. The diamonds were identified using electron microscopy and X-ray diffraction. The crystals, as a rule, represent a combination of cubes and octahedrons, with rare rhombododecahedrons. The TFE diamond has a typical cubic cell with a cube edge a = 3.574 Å and belongs to the spatial group of Fd-3m. The X-ray diffraction pattern of some grains contain reflexes with fractional indices, which indicate the twinning of the diamond along the plane {111}, which is confirmed by crystal morphological analysis. The TFE diamond was formed at the

AB - Diamond crystals 0.05-0.2 mm (rarely up to 0.7 mm) in size were found in lavas of the Tolbachik fissure eruption (TFE, Kamchatka, 2012-2013). The TFE basaltic lavas with diamonds in the pores are similar in chemical composition to the lavas of the Great Tolbachik Fissure Eruption (GTFE, Kamchatka, 1975-1976); however, the basalts of the new eruption contain slightly more SiO2 and higher Fe relative to those of GTFE. Basalts of both eruptions are close in trace element composition. The diamonds were identified using electron microscopy and X-ray diffraction. The crystals, as a rule, represent a combination of cubes and octahedrons, with rare rhombododecahedrons. The TFE diamond has a typical cubic cell with a cube edge a = 3.574 Å and belongs to the spatial group of Fd-3m. The X-ray diffraction pattern of some grains contain reflexes with fractional indices, which indicate the twinning of the diamond along the plane {111}, which is confirmed by crystal morphological analysis. The TFE diamond was formed at the

U2 - 10.1134/S1028334X14010097

DO - 10.1134/S1028334X14010097

M3 - Article

SP - 47

EP - 49

JO - Doklady Earth Sciences

JF - Doklady Earth Sciences

SN - 1028-334X

IS - 1

ER -