Using Palyanovskoye oil field of Krasnoleninsk arch we demonstrated that local cataclasis and pneumatolytic-hydrothermal metasomatism manifestations are widespread in the Paleozoic basement rocks. For the first time the earliest indications of deep fluid activity were detected – at the stage of granite deep fluid saturation and primary diffuse leaching of feldspars. During transition to the infiltration process, they comprise jet-stream fibroblast structures formed due to biotite and plagioclase resorption by amphibole and scapolite association.
