Structural control on carbon dioxide diffuse degassing at the Caviahue – Copahue Volcanic Complex, Argentina

Abstract

The Caviahue – Copahue Volcanic Complex (CCVC) is located within the Andean Cordillera, in the Neuquén province, Argentina. This tectono-magmatic system lies within the northern termination of the Liquiñe – Ofqui fault zone, a 1,200-km-long intraarc strike-slip fault system. Fluid emissions at this active volcanic complex are fed by a hydrothermal reservoir located at 800 m depth, mostly recharged by meteoric water. The reservoir is heated by a magmatic chamber located at 5 km depth, which also provides the system with magmatic gases. Fluid emissions at the CCVC release over 200 tons per day of soil diffuse CO2. The aim of this study is to evaluate the control that the local structural architecture exerts on CO2 flow, from the hydrothermal reservoir to the surface.