PETROLOGICAL PECULIARITIES OF THE ABSK INTRUSION TRAPS AND THEIR FORMATION CONDITIONS (SIBERIAN PLATFORM)

Results of petro-geochemical investigations of the Absk intrusion traps in the southern Siberian platform are presented. The presence of dolerite varieties with relatively high alkaline and silica contents is characteristic of the Absk intrusion traps. Occurrence of high alkaline rock varieties is related to different structural position of the magma conducting faults relative to magma chamber and fluid reworking of rocks as well as to local postmagmatic influence of residual deep fluid on initial dolerites. It is suggests that the plume-lithosphere interaction was the mechanism by which the Absk intrusion was formed within the trap province