Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield
Being far from plate boundaries but covered with seismograph networks, the Fennoscandian Shield features an ideal test laboratory for studies of intraplate seismicity. For this purpose, this study applies 4190 earthquake events from years 2000–2015 with magnitudes ranging from 0.10 to 5.22 in Finnis...
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ftunivhelsihelda:oai:helda.helsinki.fi:10138/232543 2024-01-07T09:43:12+01:00 Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield Veikkolainen, Toni Kukkonen, Ilmo T. Tiira, Timo Department of Physics Institute of Seismology Department of Geosciences and Geography 2018-02-17T12:12:06Z 14 application/pdf http://hdl.handle.net/10138/232543 eng eng Oxford University Press 10.1093/gji/ggx373 Veikkolainen , T , Kukkonen , I T & Tiira , T 2017 , ' Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield ' , Geophysical Journal International , vol. 211 , no. 3 , pp. 1414-1427 . https://doi.org/10.1093/gji/ggx373 ORCID: /0000-0001-9447-6146/work/41401645 ORCID: /0000-0003-2740-6185/work/41401888 85052655999 dadd6ed9-64d7-4b07-98cc-bef3fa6cad8e http://hdl.handle.net/10138/232543 000416507600009 cc_by openAccess info:eu-repo/semantics/openAccess 114 Physical sciences 1171 Geosciences Article publishedVersion 2018 ftunivhelsihelda 2023-12-14T00:01:18Z Being far from plate boundaries but covered with seismograph networks, the Fennoscandian Shield features an ideal test laboratory for studies of intraplate seismicity. For this purpose, this study applies 4190 earthquake events from years 2000–2015 with magnitudes ranging from 0.10 to 5.22 in Finnish and Swedish national catalogues. In addition, 223 heat flow determinations from both countries and their immediate vicinity were used to analyze the potential correlation of earthquake focal depths and the spatially interpolated heat flow field. Separate subset analyses were performed for five areas of notable seismic activity: the southern Gulf of Bothnia coast of Sweden (area 1), the northern Gulf of Bothnia coast of Sweden (area 2), the Swedish Norrbotten and western Finnish Lapland (area 3), the Kuusamo region of Finland (area 4) and the southernmost Sweden (area 5). In total, our subsets incorporated 3619 earthquake events. No obvious relation of heat flow and focal depth exists, implying that variations of heat flow are primarily caused by shallow lying heat producing units instead of deeper sources. This allows for construction of generic geotherms for the range of representative palaeoclimatically corrected (steady-state) surface heat flow values (40–60 mWm−2). The one-dimensional geotherms constructed for a three-layer crust and lithospheric upper mantle are based on mantle heat flow constrained with the aid of mantle xenolith thermobarometry (9–15 mWm−2), upper crustal heat production values (3.3–1.1 μWm−3), and the brittle-ductile transition temperature (350 °C) assigned to the cutoff depth of seismicity (28 ± 4 km). For the middle and lower crust heat production values of 0.6 and 0.2 μWm−3 were assigned, respectively. The models suggest a Moho temperature range of 460 to 500 °C. Being far from plate boundaries but covered with seismograph networks, the Fennoscandian Shield features an ideal test laboratory for studies of intraplate seismicity. For this purpose, this study applies 4190 earthquake events ... Article in Journal/Newspaper Fennoscandian Lapland Norrbotten HELDA – University of Helsinki Open Repository Kuusamo ENVELOPE(29.183,29.183,65.967,65.967) Geophysical Journal International 211 3 1414 1427 |
institution |
Open Polar |
collection |
HELDA – University of Helsinki Open Repository |
op_collection_id |
ftunivhelsihelda |
language |
English |
topic |
114 Physical sciences 1171 Geosciences |
spellingShingle |
114 Physical sciences 1171 Geosciences Veikkolainen, Toni Kukkonen, Ilmo T. Tiira, Timo Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield |
topic_facet |
114 Physical sciences 1171 Geosciences |
description |
Being far from plate boundaries but covered with seismograph networks, the Fennoscandian Shield features an ideal test laboratory for studies of intraplate seismicity. For this purpose, this study applies 4190 earthquake events from years 2000–2015 with magnitudes ranging from 0.10 to 5.22 in Finnish and Swedish national catalogues. In addition, 223 heat flow determinations from both countries and their immediate vicinity were used to analyze the potential correlation of earthquake focal depths and the spatially interpolated heat flow field. Separate subset analyses were performed for five areas of notable seismic activity: the southern Gulf of Bothnia coast of Sweden (area 1), the northern Gulf of Bothnia coast of Sweden (area 2), the Swedish Norrbotten and western Finnish Lapland (area 3), the Kuusamo region of Finland (area 4) and the southernmost Sweden (area 5). In total, our subsets incorporated 3619 earthquake events. No obvious relation of heat flow and focal depth exists, implying that variations of heat flow are primarily caused by shallow lying heat producing units instead of deeper sources. This allows for construction of generic geotherms for the range of representative palaeoclimatically corrected (steady-state) surface heat flow values (40–60 mWm−2). The one-dimensional geotherms constructed for a three-layer crust and lithospheric upper mantle are based on mantle heat flow constrained with the aid of mantle xenolith thermobarometry (9–15 mWm−2), upper crustal heat production values (3.3–1.1 μWm−3), and the brittle-ductile transition temperature (350 °C) assigned to the cutoff depth of seismicity (28 ± 4 km). For the middle and lower crust heat production values of 0.6 and 0.2 μWm−3 were assigned, respectively. The models suggest a Moho temperature range of 460 to 500 °C. Being far from plate boundaries but covered with seismograph networks, the Fennoscandian Shield features an ideal test laboratory for studies of intraplate seismicity. For this purpose, this study applies 4190 earthquake events ... |
author2 |
Department of Physics Institute of Seismology Department of Geosciences and Geography |
format |
Article in Journal/Newspaper |
author |
Veikkolainen, Toni Kukkonen, Ilmo T. Tiira, Timo |
author_facet |
Veikkolainen, Toni Kukkonen, Ilmo T. Tiira, Timo |
author_sort |
Veikkolainen, Toni |
title |
Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield |
title_short |
Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield |
title_full |
Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield |
title_fullStr |
Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield |
title_full_unstemmed |
Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield |
title_sort |
heat flow, seismic cutoff depth and thermal modeling of the fennoscandian shield |
publisher |
Oxford University Press |
publishDate |
2018 |
url |
http://hdl.handle.net/10138/232543 |
long_lat |
ENVELOPE(29.183,29.183,65.967,65.967) |
geographic |
Kuusamo |
geographic_facet |
Kuusamo |
genre |
Fennoscandian Lapland Norrbotten |
genre_facet |
Fennoscandian Lapland Norrbotten |
op_relation |
10.1093/gji/ggx373 Veikkolainen , T , Kukkonen , I T & Tiira , T 2017 , ' Heat flow, seismic cutoff depth and thermal modeling of the Fennoscandian Shield ' , Geophysical Journal International , vol. 211 , no. 3 , pp. 1414-1427 . https://doi.org/10.1093/gji/ggx373 ORCID: /0000-0001-9447-6146/work/41401645 ORCID: /0000-0003-2740-6185/work/41401888 85052655999 dadd6ed9-64d7-4b07-98cc-bef3fa6cad8e http://hdl.handle.net/10138/232543 000416507600009 |
op_rights |
cc_by openAccess info:eu-repo/semantics/openAccess |
container_title |
Geophysical Journal International |
container_volume |
211 |
container_issue |
3 |
container_start_page |
1414 |
op_container_end_page |
1427 |
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1787424451964436480 |