A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid
-
Upload
georg-geothermal-workshop-2016 -
Category
Engineering
-
view
4 -
download
0
Transcript of A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid
![Page 1: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/1.jpg)
SOURCES AND REACTIONS OF VOLATILES IN ICELANDIC THERMAL FLUID
Andri Stefánsson, Sæmundur A. Halldórsson, David Hilton, Árný E. Sveinbjörnsdóttir, Jaime D. Barnes, Shuhei Ono, Jan
Heinemeier, Jens Fiebig, Finnbogi Óskarsson, Peter Torssander, Stefán Arnórsson
![Page 2: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/2.jpg)
Volatiles
• Volatiles are a group of elements and compounds that typically have low boiling points and are commonly found within planetary crusts and the atmosphere. • In thermal fluids, volatile elements include for example: H,
O, C, S, Cl, F, N, B, He and other noble gases• Use isotopes to understand sources and reactions• Sampling• Analysis• Isotope geochemical modeling
![Page 3: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/3.jpg)
![Page 5: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/5.jpg)
Sampling
![Page 7: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/7.jpg)
Hekla 1980• Cl <10 to >20,000
ppm• 5-450°C• Hot springs, fumaroles
and wells
Thermal fluids
![Page 8: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/8.jpg)
Hekla 1980• 5-450°C• Hot springs, fumaroles
and wells• S <1 to >1500 ppm
Thermal fluids
![Page 9: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/9.jpg)
Hekla 1980• 5-450°C• Hot springs, fumaroles
and wells• S <1 to >1500 ppm
• CO2 <10 to >10,000 ppm
Thermal fluids
![Page 10: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/10.jpg)
Hekla 1980• 5-450°C• Hot springs, fumaroles
and wells• S <1 to >1500 ppm
• CO2 <10 to >10,000 ppm
• Meteoric and seawater water source
• Dominated by H2O (>95 mol%)
Thermal fluids
![Page 11: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/11.jpg)
• Trace sources and reactions of volatiles• Approach• Conceptual geological and
geochemical models• Data collection and
analysis• Simulations of chemical
and isotope behavior of the conceptual models• Comparison of the two
Isotopes of volatile elements
![Page 12: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/12.jpg)
Sulfur isotopes and low-temperature SO4
• Multiple oxidation states (S-II to S+VI)
• Four stable isotopes (32S, 33S, 34S and 36S)
• SO4 in low-T water on the Southern Lowlands
• Three trends:• Meteoric water SO4
source• Water-rock interaction
and SO4 in rocks• Seawater mixing
![Page 13: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/13.jpg)
Sulfur isotopes and low-temperature SO4
• Multiple oxidation states (S-II to S+VI)
• Four stable isotopes (32S, 33S, 34S and 36S)
• SO4 in low-T water on the Southern Lowlands
• Three trends:• Meteoric water SO4
source• Water-rock interaction
and SO4 in rocks• Seawater mixing
![Page 14: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/14.jpg)
Hekla 1980
Sulfur isotopes and low-temperature SO4
Chlorine δ34S (sulfate)
![Page 15: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/15.jpg)
Carbon in low- and high-temperature fluid
• Multiple oxidation states (C-IV to C+IV)
• Two stable isotopes (12C, 13C)
• Both as gas phase and liquid phase
• Fluid-rock interaction a major source of CO2
• Melt (mantle) CO2 input on- and off-rift
![Page 16: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/16.jpg)
Carbon in low- and high-temperature fluid
• Multiple oxidation states (C-IV to C+IV)
• Two stable isotopes (12C, 13C)
• Both as gas phase and liquid phase
• Fluid-rock interaction a major source of CO2
• Melt (mantle) CO2 input on- and off-rift
![Page 17: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/17.jpg)
Hekla 1980
Carbon in low- and high-temperature fluid
![Page 18: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/18.jpg)
Helium isotopes
• 3He dominates the atmosphere where 4He is produced by decay of heavy elements in Earth
• He is non-reactive (as well as other noble gases) – can be used to look at source(s) and source(s) heterogeneity
• Values given relative to air, RA
• MORB is ~8• Higher values indicate
primordial mantle (early earth) input
RA
0 5 10 15 20 25 30
Count
0
20
40
60
80
100
![Page 19: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/19.jpg)
Hekla 1980
Helium in low- and high-temperature fluid
![Page 20: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/20.jpg)
![Page 21: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/21.jpg)
![Page 22: A3 Andri Stefansson Sources and reactions to volatiles in Iceladnc thermal Fluid](https://reader035.fdocuments.net/reader035/viewer/2022070514/587d2a8e1a28ab1c2f8b75cb/html5/thumbnails/22.jpg)
Sæmi A. Halldórsson
Andri Stefánsson
Shuhei Ono
David R.Hilton
Árný E.Sveinbjörnsdóttir
Jaime D. Barnes
Jan Heinemeier Jens Fiebig Finnbogi Óskarsson
Peter Torssander
Stefán Arnórsson