Relationship between ore zones and porphyritic intrusions in the Leninogorsk ore field

Abstract

Among the flat-lying middle Paleozoic formations in the Leninogorsk ore field, layered bodies of porphyries of supposedly Early Carboniferous age occupy significant space. From the flanks toward the center of the ore field, these bodies gradually wedge out and branch in the section into a series of gently inclined apophyses (sills). Around two such apophyses, which in the southeast and northeast reach the center of the ore field (the Ridder-Sokol'noye deposit), a system of gently inclined veins, consisting of explosion-hydrothermal breccias and sericitolites (hydrothermalites), and also aureoles of microquartzites and pyritic polymetallic ores (the Western and Eastern oppositely directed oremagmatic clusters respectively) are developed. The ore zones in the clusters are located Immediately on the extension or above (and below) the segregations of hydrothermalites. The origin of the mineralization has been controlled by the injection, differentiation, and crystallization of porphyritic magmas, and by the r...