Abstract

A model is presented dealing with the relations between convection in the continental crust and the formation of lode Au deposits. Sufficient permeability exists in the brittle rheologic regime in large sections of the continental crust to permit convection of meteoric water on both local and regional scales. The solubility of Au in this fluid is high enough to permit the mobilization of quantities of Au which are sufficient to form ore-grade deposits. This general process is shown to be responsible for a continuous series of deposit types ranging rom 1-2-km-deep epithermal deposits, to intermediate-depth Carlin-type deposits, to 10-12-km-deep mesothermal deposits. Major geologic and geochemical differences among the deposit types are products of fluid convection at variable depths and the resulting effects on water/rock ratios and gas solubilities.

First Page Preview

First page PDF preview
You do not currently have access to this article.