MODELING OF GEOCHEMICAL PROCESSES THAT OCCURRED DURING THE FORMATION OF THE SCHLEMA DEPOSIT, ERZGEBIRGE. I. SYNMINERALIZATION PROCESSES IN THE AUE GRANITES

Abstract

The geochemical events that occurred within the outlines of the Schlema ore field during the formation of vein bodies cannot be understood without considering the processes that occurred synchronously in the footwall zone, in the Aue granite cupola, from where mineral-forming thermal solutions ascended into the deposit. It is known that the upper part of the cupola experienced hydrothermal alterations, which had a minor influence on the appearance of the rocks, but caused a number of important geochemical consequences: an increase in the degree of iron and sulfur oxidation in grantie, the replacement of accessory sulfides by oxygenbearing salts, etc. These changes were analyzed using computer models for a decrease in T and P of the granitewater system from 400°C (3.0-1.5 kbar) to 140°C (2.0-0.2 kbar). The role of these changes in the fate of disseminated ore elements of granite and in the extraction of ore elements from the changing rock into the equilibrium pore solution was evaluated. © Pleiades Publishing, Inc. 2006.