UNU-GTP MSc Fellows graduating in 2011. From left: Andi Joko Nugroho (Indonesia), Andemariam Teklesenbet (Eritrea), Endy Kevin Padilla Rivas (El Salvador), Alejandro Rodríguez Badilla (Costa Rica)
On Thurdsay 12th May, Endy Kevin Padilla Rivas will defend his work for the degree of Master of Science. The thesis is entitled: „Transport and precipitation of carbon and
sulphur in the Reykjanes geothermal system, Iceland“.
The defence will take place in room A131 in Askja and starts at 15.00. The Supervisor on the project is Andri Stefánsson from the University of Iceland and Thráinn Fridriksson
from Iceland GeoSurvey and the external examiner is Vigdís Hardardóttir from Iceland GeoSurvey.
Kevins thesis deals with the geochemistry of carbon and sulphur in the Reykjanes geothermal system. Based on existing data on fluid chemistry and alteration mineralogy, measurements
of of carbon, sulphide and sulphate concentrations in well cuttings and geochemical modelling the interaction between magma gasses, geothermal fluids and rocks were carried out as well
as the effects of cooling and boiling on the transport and precipitation of carbon, sulphide and sulphate. The concentrations of H2S and SO4 in the aquifer fluids at 275-310°C is
likely controlled by mineral-buffer reactions whereas the concentration of CO2 may also be effected by magma gas supply. Upon cooling and boiling, sulphide minerals have the
potential to form whereas carbonate precipitation is only favoured upon boiling. This is in reasonable agreement with sulphide minerals observed at various depths thought-out the
system whereas carbonates are building up accompanying boiling. Based on mass-balancecalculations the sulphide, sulphate and carbonate mineralization rates correspond to 1100,
500 and 1000 tonne per year during the last 12-20 thousand years, respectively.
