Phosphorus in Mesozoic intrusives in the region of the Seligdar apatite deposit

Phosphorus distributions are given for Central Aldan Mesozoic magmatites, mainly for the dike complex within the Seligdar apatite-carbonate ore deposit. The highest phosphate levels occur in the pyroxenites of the leucitite-syenite subassociation, but these rocks occur only on a restricted scale. The trachyte dikes have assimilated phosphorus from the surrounding apatite ores with the formation of an aureole of dike rocks anomalous in P₂O₅, including those in the upper structural level above the deposit. The assimilation is accompanied by calcitization in the dikes and by dedolomitization in the surrounding ores, where apatite calcite rocks are formed. -Journal summary