Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland
International audience Electrical conductivity and polarization properties of 6 samples from Krafla volcano (Iceland) were measured in the frequency range 1 mHz-45 kHz and compared to the data obtained on various basaltic rock samples from Ha-waii. The results indicate that for altered samples, the...
Published in: | Journal of Volcanology and Geothermal Research |
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Main Authors: | , , , , , , |
Other Authors: | , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2018
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Online Access: | https://hal.science/hal-02324352 https://hal.science/hal-02324352/document https://hal.science/hal-02324352/file/2018-JVGR-induced%20polarization%20Krafla.pdf https://doi.org/10.1016/j.jvolgeores.2018.11.008 |
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Open Polar |
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Université de Lyon: HAL |
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English |
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[SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Revil, A. Qi, Y. Ghorbani, A. Ahmed, A, Soueid Ricci, T. Labazuy, P. Soueid Ahmed, A. Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland |
topic_facet |
[SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Electrical conductivity and polarization properties of 6 samples from Krafla volcano (Iceland) were measured in the frequency range 1 mHz-45 kHz and compared to the data obtained on various basaltic rock samples from Ha-waii. The results indicate that for altered samples, the surface conductivity, normalized chargeability, and quad-rature conductivity of the core samples scales linearly with the cation exchange capacity, taken as a proxy of the alteration facies. The surface conductivity of fresh samples is also controlled by the cation exchange capacity but their normalized chargeability is influenced by the presence of magnetite, especially for unaltered samples. The temperature dependence of quadrature conductivity and normalized chargeability can be modeled with an Ar-rhenius equation with an activation energy of 16-19 kJ mol −1. The experimental results agree with a model in which the polarization of the metallic and non-metallic grains are both considered in a unified framework. These results are used to interpret two 3D induced polarization surveys performed in the South and East parts of Krafla volcano using two 1.3 km-long cables with 32 electrodes each. The electrical conductivity is in the range 0.3 (clay cap) to 5 × 10 −5 S m −1 (unaltered rock) while the normalized chargeability is typically comprised between 10 −2 (clay cap) and 10 −5 S m −1 (unaltered rock). Induced polarization is used to image porosity and the cation exchange capacity. A long 5.6 km electrical conductivity profile was also performed connecting the two 3D sites and crossing a rhyolitic obsidian ridge called Hrafntinnuhryggur. Hrafntinnuhryggur is characterized by very low conductivity values on the order of 10 −4 S m −1. The long conductivity profile shows the position of the inner and outer caldera rims and the feeder dike of Hrafntinnuhryggur. A self-potential survey performed along this long profile shows no shallow active geothermal features in this area, as expected from the low perme-ability of the ... |
author2 |
Department of Geophysics Golden CO Colorado School of Mines Department of Minning and Metallurgy, Yazd University Department of Minning and Metallurgy Laboratoire Magmas et Volcans (LMV) Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) Morphodynamique Continentale et Côtière (M2C) Université de Caen Normandie (UNICAEN) Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN) Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Revil, A. Qi, Y. Ghorbani, A. Ahmed, A, Soueid Ricci, T. Labazuy, P. Soueid Ahmed, A. |
author_facet |
Revil, A. Qi, Y. Ghorbani, A. Ahmed, A, Soueid Ricci, T. Labazuy, P. Soueid Ahmed, A. |
author_sort |
Revil, A. |
title |
Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland |
title_short |
Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland |
title_full |
Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland |
title_fullStr |
Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland |
title_full_unstemmed |
Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland |
title_sort |
electrical conductivity and induced polarization investigations at krafla volcano, iceland |
publisher |
HAL CCSD |
publishDate |
2018 |
url |
https://hal.science/hal-02324352 https://hal.science/hal-02324352/document https://hal.science/hal-02324352/file/2018-JVGR-induced%20polarization%20Krafla.pdf https://doi.org/10.1016/j.jvolgeores.2018.11.008 |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
ISSN: 0377-0273 Journal of Volcanology and Geothermal Research https://hal.science/hal-02324352 Journal of Volcanology and Geothermal Research, 2018, 368, pp.73-90. ⟨10.1016/j.jvolgeores.2018.11.008⟩ |
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info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jvolgeores.2018.11.008 hal-02324352 https://hal.science/hal-02324352 https://hal.science/hal-02324352/document https://hal.science/hal-02324352/file/2018-JVGR-induced%20polarization%20Krafla.pdf doi:10.1016/j.jvolgeores.2018.11.008 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1016/j.jvolgeores.2018.11.008 |
container_title |
Journal of Volcanology and Geothermal Research |
container_volume |
368 |
container_start_page |
73 |
op_container_end_page |
90 |
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1810451698436538368 |
spelling |
ftunivlyon:oai:HAL:hal-02324352v1 2024-09-15T18:13:55+00:00 Electrical conductivity and induced polarization investigations at Krafla volcano, Iceland Revil, A. Qi, Y. Ghorbani, A. Ahmed, A, Soueid Ricci, T. Labazuy, P. Soueid Ahmed, A. Department of Geophysics Golden CO Colorado School of Mines Department of Minning and Metallurgy, Yazd University Department of Minning and Metallurgy Laboratoire Magmas et Volcans (LMV) Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) Morphodynamique Continentale et Côtière (M2C) Université de Caen Normandie (UNICAEN) Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN) Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS) 2018-12 https://hal.science/hal-02324352 https://hal.science/hal-02324352/document https://hal.science/hal-02324352/file/2018-JVGR-induced%20polarization%20Krafla.pdf https://doi.org/10.1016/j.jvolgeores.2018.11.008 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jvolgeores.2018.11.008 hal-02324352 https://hal.science/hal-02324352 https://hal.science/hal-02324352/document https://hal.science/hal-02324352/file/2018-JVGR-induced%20polarization%20Krafla.pdf doi:10.1016/j.jvolgeores.2018.11.008 info:eu-repo/semantics/OpenAccess ISSN: 0377-0273 Journal of Volcanology and Geothermal Research https://hal.science/hal-02324352 Journal of Volcanology and Geothermal Research, 2018, 368, pp.73-90. ⟨10.1016/j.jvolgeores.2018.11.008⟩ [SDU]Sciences of the Universe [physics] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2018 ftunivlyon https://doi.org/10.1016/j.jvolgeores.2018.11.008 2024-07-08T23:59:54Z International audience Electrical conductivity and polarization properties of 6 samples from Krafla volcano (Iceland) were measured in the frequency range 1 mHz-45 kHz and compared to the data obtained on various basaltic rock samples from Ha-waii. The results indicate that for altered samples, the surface conductivity, normalized chargeability, and quad-rature conductivity of the core samples scales linearly with the cation exchange capacity, taken as a proxy of the alteration facies. The surface conductivity of fresh samples is also controlled by the cation exchange capacity but their normalized chargeability is influenced by the presence of magnetite, especially for unaltered samples. The temperature dependence of quadrature conductivity and normalized chargeability can be modeled with an Ar-rhenius equation with an activation energy of 16-19 kJ mol −1. The experimental results agree with a model in which the polarization of the metallic and non-metallic grains are both considered in a unified framework. These results are used to interpret two 3D induced polarization surveys performed in the South and East parts of Krafla volcano using two 1.3 km-long cables with 32 electrodes each. The electrical conductivity is in the range 0.3 (clay cap) to 5 × 10 −5 S m −1 (unaltered rock) while the normalized chargeability is typically comprised between 10 −2 (clay cap) and 10 −5 S m −1 (unaltered rock). Induced polarization is used to image porosity and the cation exchange capacity. A long 5.6 km electrical conductivity profile was also performed connecting the two 3D sites and crossing a rhyolitic obsidian ridge called Hrafntinnuhryggur. Hrafntinnuhryggur is characterized by very low conductivity values on the order of 10 −4 S m −1. The long conductivity profile shows the position of the inner and outer caldera rims and the feeder dike of Hrafntinnuhryggur. A self-potential survey performed along this long profile shows no shallow active geothermal features in this area, as expected from the low perme-ability of the ... Article in Journal/Newspaper Iceland Université de Lyon: HAL Journal of Volcanology and Geothermal Research 368 73 90 |