Zeolite Zoning in Drill Holes of the Copahue Geothermal Field, Neuquen, Argentina

Abstract

The objective of this work is the study of the zeolite zoning in the Copahue Geothermal Field, and the relation between the zoning with temperature, pressure, composition, etc. The most common zeolites in Copahue are stilbite, laumontite, and wairakite. Depth zonation of secondary minerals were delineated for Ca zeolites as: The two former occur at temperatures below whereas the latter, accompanied by epidote, prehnite, garnet, chlorite and tremolite, occurs within a range of temperatures from to greater than In addition to these common zeolites; mordenite, clinoptilolite, heulandite and others, were also identified. The Occurrence of wairakite in the reservoir zone coexisting other Ca-AI silicates, indicates that thermal waters at depth are hot and neutral to slightly alkaline and that is rather low. It also strongly suggests a good path for the vapor.