Istituto di Geoscienze e Georisorse     
Aguilera F., Tassi F., Darrah T., Moune S., Vaselli O. Geochemical model of a magmatic-hydrothermal system at the Lastarria volcano, northern Chile. In: Bulletin of volcanology, vol. 74 (1) pp. 119 - 134. Springer, 2012.
Lastarria volcano (2510′ S, 6831′ W; 5,697m  above sea level), located in the Central Andes Volcanic Zone (northern Chile), is characterized by four distinct fumarolic fields with outlet temperatures ranging between 80C and 408C as measured between May 2006-March 2008 and April-June 2009. Fumarolic gasses contain significant concentrations of high temperature gas compounds (i.e., SO2, HCl, HF, H2, and CO), and isotopic ratios (3He/4He, δ13C-CO2, δ18O-H2O, and δD-H2O) diagnostic of magmatic gas sources. Gas equilibria systematics, in both the H2O-H2-CO2-CO-CH4 and alkane-alkene C3 system, suggest that Lastarria fumarolic gasses emanate from a superheated vapor that is later cooled and condensed at relatively shallow depths. This two-stage process inhibits the formation of a continuous aquifer (e.g., horizontal liquid layer) at relatively shallow depth. Recent developments in the magmatic gas system may have enhanced the transfer and release of heat causing shallow aquifer vaporization. The consequent pressure increase and aquifer vaporization likely triggered the inflation events beginning in 2003 at the Lastarria volcano.
URL: http://www.springerlink.com/openurl.asp?genre=journal&issn=0258-8900
Subject Lastarria volcano
fumarolic gas
ground deformation
fluid geochemistry
Andean volcanics

Icona documento 1) Download Document PDF

Icona documento Open access Icona documento Restricted Icona documento Private


Per ulteriori informazioni, contattare: Librarian http://puma.isti.cnr.it

Valid HTML 4.0 Transitional