Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland
SUMMARY Occurrence of seismicity sequences as consequence of fluid injection or extraction has long been studied and documented. Causal relations between injection parameters, such as injection pressure, injection rates, total injected volumes and injectivity, with seismicity derived parameters, suc...
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Online Access: | http://dx.doi.org/10.1093/gji/ggab423 http://academic.oup.com/gji/advance-article-pdf/doi/10.1093/gji/ggab423/40751333/ggab423.pdf https://academic.oup.com/gji/article-pdf/228/3/1866/41395425/ggab423.pdf |
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croxfordunivpr:10.1093/gji/ggab423 2024-04-07T07:53:28+00:00 Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland Duboeuf, Laure Dichiarante, Anna Maria Oye, Volker Research Council of Norway 2021 http://dx.doi.org/10.1093/gji/ggab423 http://academic.oup.com/gji/advance-article-pdf/doi/10.1093/gji/ggab423/40751333/ggab423.pdf https://academic.oup.com/gji/article-pdf/228/3/1866/41395425/ggab423.pdf en eng Oxford University Press (OUP) https://creativecommons.org/licenses/by/4.0/ Geophysical Journal International volume 228, issue 3, page 1866-1886 ISSN 0956-540X 1365-246X Geochemistry and Petrology Geophysics journal-article 2021 croxfordunivpr https://doi.org/10.1093/gji/ggab423 2024-03-08T03:07:39Z SUMMARY Occurrence of seismicity sequences as consequence of fluid injection or extraction has long been studied and documented. Causal relations between injection parameters, such as injection pressure, injection rates, total injected volumes and injectivity, with seismicity derived parameters, such as seismicity rate, cumulative seismic moment, distance of seismicity (RT-plot), b-values, etc. have been derived. In addition, reservoir engineering parameters such as permeability/porosity relations and flow types play a role together with geology knowledge on fault and fracture properties, influenced by the stress field on different scales. In this paper, we study observed seismicity related to water injection at the Reykjanes Geothermal Field, Iceland. The region near the injection well did not experience seismicity before the start of injection. However, we observed continued seismic activity during the 3 months of injection in 2015, resulting in a cloud of about 700 events ranging in magnitude from Mw 0.7 to 3.3. We re-located these events using a modified double-difference algorithm and determined focal mechanism of event subsets. Characteristic for the site is that the events are bound to about 4 km distance to the injection point, and moreover known faults seem to act as barrier to fluids and seismicity. Several repeating sequences of seismicity, defined as bursts of seismicity have hypocenter migration velocities larger than 4 km d–1 and their dominant direction of propagation is away from the injection point towards larger depths. The seismic events within the bursts lack larger magnitude events, have elevated b-values (∼1.5) and consist of many multiplets. Except from the coinciding onset of seismicity with the start of fluid injection, no correlation between injection rates and volumes could be identified, neither could hydraulic diffusivity models explain observed seismicity patterns. Comparison of our results with investigations on background seismicity from 1995 to 2019 and from a seismic swarm in ... Article in Journal/Newspaper Iceland Oxford University Press Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) Geophysical Journal International 228 3 1866 1886 |
institution |
Open Polar |
collection |
Oxford University Press |
op_collection_id |
croxfordunivpr |
language |
English |
topic |
Geochemistry and Petrology Geophysics |
spellingShingle |
Geochemistry and Petrology Geophysics Duboeuf, Laure Dichiarante, Anna Maria Oye, Volker Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland |
topic_facet |
Geochemistry and Petrology Geophysics |
description |
SUMMARY Occurrence of seismicity sequences as consequence of fluid injection or extraction has long been studied and documented. Causal relations between injection parameters, such as injection pressure, injection rates, total injected volumes and injectivity, with seismicity derived parameters, such as seismicity rate, cumulative seismic moment, distance of seismicity (RT-plot), b-values, etc. have been derived. In addition, reservoir engineering parameters such as permeability/porosity relations and flow types play a role together with geology knowledge on fault and fracture properties, influenced by the stress field on different scales. In this paper, we study observed seismicity related to water injection at the Reykjanes Geothermal Field, Iceland. The region near the injection well did not experience seismicity before the start of injection. However, we observed continued seismic activity during the 3 months of injection in 2015, resulting in a cloud of about 700 events ranging in magnitude from Mw 0.7 to 3.3. We re-located these events using a modified double-difference algorithm and determined focal mechanism of event subsets. Characteristic for the site is that the events are bound to about 4 km distance to the injection point, and moreover known faults seem to act as barrier to fluids and seismicity. Several repeating sequences of seismicity, defined as bursts of seismicity have hypocenter migration velocities larger than 4 km d–1 and their dominant direction of propagation is away from the injection point towards larger depths. The seismic events within the bursts lack larger magnitude events, have elevated b-values (∼1.5) and consist of many multiplets. Except from the coinciding onset of seismicity with the start of fluid injection, no correlation between injection rates and volumes could be identified, neither could hydraulic diffusivity models explain observed seismicity patterns. Comparison of our results with investigations on background seismicity from 1995 to 2019 and from a seismic swarm in ... |
author2 |
Research Council of Norway |
format |
Article in Journal/Newspaper |
author |
Duboeuf, Laure Dichiarante, Anna Maria Oye, Volker |
author_facet |
Duboeuf, Laure Dichiarante, Anna Maria Oye, Volker |
author_sort |
Duboeuf, Laure |
title |
Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland |
title_short |
Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland |
title_full |
Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland |
title_fullStr |
Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland |
title_full_unstemmed |
Interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the Reykjanes Geothermal Field, Iceland |
title_sort |
interplay of large-scale tectonic deformation and local fluid injection investigated through seismicity patterns at the reykjanes geothermal field, iceland |
publisher |
Oxford University Press (OUP) |
publishDate |
2021 |
url |
http://dx.doi.org/10.1093/gji/ggab423 http://academic.oup.com/gji/advance-article-pdf/doi/10.1093/gji/ggab423/40751333/ggab423.pdf https://academic.oup.com/gji/article-pdf/228/3/1866/41395425/ggab423.pdf |
long_lat |
ENVELOPE(-22.250,-22.250,65.467,65.467) |
geographic |
Reykjanes |
geographic_facet |
Reykjanes |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Geophysical Journal International volume 228, issue 3, page 1866-1886 ISSN 0956-540X 1365-246X |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1093/gji/ggab423 |
container_title |
Geophysical Journal International |
container_volume |
228 |
container_issue |
3 |
container_start_page |
1866 |
op_container_end_page |
1886 |
_version_ |
1795669353686892544 |