Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile
Triple oxygen isotope analyses were made on geothermal fluids and precipitates from Chile and Iceland to calibrate the silica-water isotopic fractionation for abiotic silica formation at elevated temperatures and were used to evaluate potential fractionation effects of biogenic vs. abiogenic samples...
Published in: | Geochimica et Cosmochimica Acta |
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Online Access: | https://doi.org/10.1016/j.gca.2018.05.007 https://repositorio.uchile.cl/handle/2250/151308 |
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ftunivchile:oai:repositorio.uchile.cl:2250/151308 2023-05-15T16:49:04+02:00 Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile Wostbrock, Jordan Sharp, Zachary Sánchez Yáñez, Camilo Reich Morales, Martín Van den Heuvel, Daniela Benning, Liane 2018 application/pdf https://doi.org/10.1016/j.gca.2018.05.007 https://repositorio.uchile.cl/handle/2250/151308 en eng Elsevier Geochimica et Cosmochimica Acta 234 (2018) 84–97 0016-7037 doi:10.1016/j.gca.2018.05.007 https://repositorio.uchile.cl/handle/2250/151308 Attribution-NonCommercial-NoDerivs 3.0 Chile http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ CC-BY-NC-ND Geochimica et Cosmochimica Acta Triple oxygen isotope fractionation Silica solubility Equilibrium fractionation Quartz-water Artículo de revista 2018 ftunivchile https://doi.org/10.1016/j.gca.2018.05.007 2023-01-08T00:50:29Z Triple oxygen isotope analyses were made on geothermal fluids and precipitates from Chile and Iceland to calibrate the silica-water isotopic fractionation for abiotic silica formation at elevated temperatures and were used to evaluate potential fractionation effects of biogenic vs. abiogenic samples and polymorphism. Coexisting water and amorphous silica precipitated inside the heat exchanger of the Hellisheioi power plant at 60 and 118 degrees C have triple oxygen isotope fractionations in excellent agreement with previous results from analyses of biogenic silica precipitated in cold waters. In contrast to samples from the geothermal plant, natural amorphous silica precipitates and waters formed in active hot springs (T = 63-84 degrees C) in the Puchuldiza geothermal area of northern Chile gave temperature estimates from the silicawater thermometer far lower (37-46 degrees C) than the measured water temperatures. Active silica precipitation was found to only occur at and above the air-water interface on glass slides placed in the hot spring waters for 9 days. The calculated temperatures and visual inspection suggest that precipitation occurred along channel edges when saturation was overstepped by a factor of two. In contrast to the surficial neoformed amorphous silica, subsurface silica samples (>10 cm) have recrystallized to opal-CT and quartz within a sinter mound and these samples preserve isotope temperatures of 82 degrees C and 89 degrees C, in good agreement with the ambient temperatures of the thermal spring conduit system. The delta O-18 values of abiogenic, low temperature silica formed in spring water far from the thermal waters with a measured temperature of 19 degrees C correspond to a silica-water temperature estimate of 20 degrees C. All samples preserved isotope data corresponding to their expected formation temperatures and appear to be in equilibrium in the triple oxygen isotope system. A best-fit theta-T relationship for silica-water using our inorganic silica-water samples is theta = ... Article in Journal/Newspaper Iceland Universidad de Chile: Repositorio académico Geochimica et Cosmochimica Acta 234 84 97 |
institution |
Open Polar |
collection |
Universidad de Chile: Repositorio académico |
op_collection_id |
ftunivchile |
language |
English |
topic |
Triple oxygen isotope fractionation Silica solubility Equilibrium fractionation Quartz-water |
spellingShingle |
Triple oxygen isotope fractionation Silica solubility Equilibrium fractionation Quartz-water Wostbrock, Jordan Sharp, Zachary Sánchez Yáñez, Camilo Reich Morales, Martín Van den Heuvel, Daniela Benning, Liane Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile |
topic_facet |
Triple oxygen isotope fractionation Silica solubility Equilibrium fractionation Quartz-water |
description |
Triple oxygen isotope analyses were made on geothermal fluids and precipitates from Chile and Iceland to calibrate the silica-water isotopic fractionation for abiotic silica formation at elevated temperatures and were used to evaluate potential fractionation effects of biogenic vs. abiogenic samples and polymorphism. Coexisting water and amorphous silica precipitated inside the heat exchanger of the Hellisheioi power plant at 60 and 118 degrees C have triple oxygen isotope fractionations in excellent agreement with previous results from analyses of biogenic silica precipitated in cold waters. In contrast to samples from the geothermal plant, natural amorphous silica precipitates and waters formed in active hot springs (T = 63-84 degrees C) in the Puchuldiza geothermal area of northern Chile gave temperature estimates from the silicawater thermometer far lower (37-46 degrees C) than the measured water temperatures. Active silica precipitation was found to only occur at and above the air-water interface on glass slides placed in the hot spring waters for 9 days. The calculated temperatures and visual inspection suggest that precipitation occurred along channel edges when saturation was overstepped by a factor of two. In contrast to the surficial neoformed amorphous silica, subsurface silica samples (>10 cm) have recrystallized to opal-CT and quartz within a sinter mound and these samples preserve isotope temperatures of 82 degrees C and 89 degrees C, in good agreement with the ambient temperatures of the thermal spring conduit system. The delta O-18 values of abiogenic, low temperature silica formed in spring water far from the thermal waters with a measured temperature of 19 degrees C correspond to a silica-water temperature estimate of 20 degrees C. All samples preserved isotope data corresponding to their expected formation temperatures and appear to be in equilibrium in the triple oxygen isotope system. A best-fit theta-T relationship for silica-water using our inorganic silica-water samples is theta = ... |
format |
Article in Journal/Newspaper |
author |
Wostbrock, Jordan Sharp, Zachary Sánchez Yáñez, Camilo Reich Morales, Martín Van den Heuvel, Daniela Benning, Liane |
author_facet |
Wostbrock, Jordan Sharp, Zachary Sánchez Yáñez, Camilo Reich Morales, Martín Van den Heuvel, Daniela Benning, Liane |
author_sort |
Wostbrock, Jordan |
title |
Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile |
title_short |
Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile |
title_full |
Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile |
title_fullStr |
Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile |
title_full_unstemmed |
Calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in Iceland and Chile |
title_sort |
calibration and application of silica-water triple oxygen isotope thermometry to geothermal systems in iceland and chile |
publisher |
Elsevier |
publishDate |
2018 |
url |
https://doi.org/10.1016/j.gca.2018.05.007 https://repositorio.uchile.cl/handle/2250/151308 |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Geochimica et Cosmochimica Acta |
op_relation |
Geochimica et Cosmochimica Acta 234 (2018) 84–97 0016-7037 doi:10.1016/j.gca.2018.05.007 https://repositorio.uchile.cl/handle/2250/151308 |
op_rights |
Attribution-NonCommercial-NoDerivs 3.0 Chile http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ |
op_rightsnorm |
CC-BY-NC-ND |
op_doi |
https://doi.org/10.1016/j.gca.2018.05.007 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
234 |
container_start_page |
84 |
op_container_end_page |
97 |
_version_ |
1766039139560456192 |