AVERAGE COMPOSITION OF BASALTS FROM THE NORTHWESTERN PART OF THE SIBERIAN CRATON

Abstract

The Siberian craton abounds with traps of different facies, and may be regarded in this respect as a standard. Permian-Triassic traps are most common here, so we primarily use them to characterize the volcanisms of the craton. To calculate the average composition of the basalts of the Siberian craton, we sampled its northwestern part for two reasons. The average chemical composition of the basalts of the northwestern part of the Siberian craton was calculated as the weighted average per formation thickness. Such an approach is more accurate than the method of calculating the arithmetic mean itself, because rock types were included in our sample in proportion to their abundance rather than to the number of analyses available for them.