Аннотация:To understand the origin of the Siberian trap province, it is necessary to know its
internal structure in detail. Only two areas were described, the Noril’sk and Maimecha-Kotuy,
while the most important part of the province, the Tunguska syneclise, is still poorly
characterized. The main goal of our study is an investigation of the structure and geochemistry
of volcanic rocks located in the central part of the province. We have studied basalts and tuffs
and compared them with the rocks of the Noril’sk area. All studied rocks belong to three
formations: Korvunchansky, Nidymsky and Kochechumsky. The whole thickness of this crosssection
is around 1,000 m. Our geochemical data demonstrate that the lower part of the crosssection
comprises basalts with TiO2 =1 wt% while the upper part consists of the basalts with
the average TiO2 content 1.4-1.5wt%. Based on this data, these rocks can be correlated with
Morongovsky and Mokulaevsky formations located in the Noril’sk area. Despite many
similarities between the volcanic rocks of these two areas, the basalts and tuffs of the Tunguska
syneclise have their specific features, i.e. many tuff horizons, small thickness of flows and their poikiloophitic structure