Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Cr-spinel assemblage from the Upper Triassic gritstones of the northeastern Siberian Platform. / Nikolenko, E. I.; Logvinova, A. M.; Izokh, A. E. и др.
в: Russian Geology and Geophysics, Том 59, № 10, 01.10.2018, стр. 1348-1364.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Cr-spinel assemblage from the Upper Triassic gritstones of the northeastern Siberian Platform
AU - Nikolenko, E. I.
AU - Logvinova, A. M.
AU - Izokh, A. E.
AU - Afanas'ev, V. P.
AU - Oleynikov, O. B.
AU - Biller, A. Ya
PY - 2018/10/1
Y1 - 2018/10/1
N2 - An assemblage of Cr-spinels widespread in Carnian (Upper Triassic) diamondiferous deposits in the northeastern Siberian Platform is studied. Analysis of their morphology and chemical composition has revealed two dominant varieties of Cr-spinels and has demonstrated certain regularities in their distribution in the study area. Correlations have been established between the areal distribution of the recognized types of Cr-spinels and diamond varieties typical of kimberlite sources and between the distribution of Cr-spinels and rounded diamond dodecahedrons. The phase and chemical compositions of polyphase inclusions in the Cr-spinels are studied. The spatial arrangement of inclusions along the crystal growth zones indicates their primary genesis and trapping from the melt during crystallization. Compositional features of some minerals in the inclusions—SiO2 impurity in apatite and high CaO contents (0.2-0.8 wt.%) in olivines—point to a nonkimberlite source of these Cr-spinels. The presence of K- and Na-containing phases and calcite in the inclusions indicates saturation of the initial melt with alkalies, Ca, and CO2. The data obtained suggest that the numerous Late Vendian diatremes in K-rich alkaline basites of the Olenek Uplift area are the source of the dominant Cr-spinel variety.
AB - An assemblage of Cr-spinels widespread in Carnian (Upper Triassic) diamondiferous deposits in the northeastern Siberian Platform is studied. Analysis of their morphology and chemical composition has revealed two dominant varieties of Cr-spinels and has demonstrated certain regularities in their distribution in the study area. Correlations have been established between the areal distribution of the recognized types of Cr-spinels and diamond varieties typical of kimberlite sources and between the distribution of Cr-spinels and rounded diamond dodecahedrons. The phase and chemical compositions of polyphase inclusions in the Cr-spinels are studied. The spatial arrangement of inclusions along the crystal growth zones indicates their primary genesis and trapping from the melt during crystallization. Compositional features of some minerals in the inclusions—SiO2 impurity in apatite and high CaO contents (0.2-0.8 wt.%) in olivines—point to a nonkimberlite source of these Cr-spinels. The presence of K- and Na-containing phases and calcite in the inclusions indicates saturation of the initial melt with alkalies, Ca, and CO2. The data obtained suggest that the numerous Late Vendian diatremes in K-rich alkaline basites of the Olenek Uplift area are the source of the dominant Cr-spinel variety.
KW - alkaline magmatism
KW - Carnian Stage
KW - diamond
KW - sedimentary reservoir
KW - Siberian Platform
KW - spinel
KW - Triassic
KW - KIMBERLITES
KW - DIAMOND
KW - ROCKS
KW - CHROME SPINEL
KW - U-PB
KW - MANTLE
KW - POLAR SIBERIA
KW - MELT INCLUSIONS
KW - AGE
KW - OLIVINE
UR - http://www.scopus.com/inward/record.url?scp=85054919933&partnerID=8YFLogxK
U2 - 10.1016/j.rgg.2018.09.011
DO - 10.1016/j.rgg.2018.09.011
M3 - Article
AN - SCOPUS:85054919933
VL - 59
SP - 1348
EP - 1364
JO - Russian Geology and Geophysics
JF - Russian Geology and Geophysics
SN - 1068-7971
IS - 10
ER -
ID: 17114977