Volcanological studies of Neogene flood basalt groups in eastern Iceland
Included in the supplementary files are seven photogrammetric panels and one geological map (1:100 000) of eastern Iceland. Flood basalt groups in the Neogene lava piles of eastern Iceland are subject to investigation. The groups form the stratigraphic section above the Reyðarfjörður central volcano...
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2015
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Online Access: | http://hdl.handle.net/1946/22929 |
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ftskemman:oai:skemman.is:1946/22929 2023-05-15T16:46:24+02:00 Volcanological studies of Neogene flood basalt groups in eastern Iceland Eldfjallafræði flæðibasaltsyrpa frá míósen á Austfjörðum Birgir Vilhelm Óskarsson 1982- Háskóli Íslands 2015-06 application/pdf application/octet-stream http://hdl.handle.net/1946/22929 en eng http://hdl.handle.net/1946/22929 Doktorsritgerðir Thesis Doctoral 2015 ftskemman 2022-12-11T06:50:05Z Included in the supplementary files are seven photogrammetric panels and one geological map (1:100 000) of eastern Iceland. Flood basalt groups in the Neogene lava piles of eastern Iceland are subject to investigation. The groups form the stratigraphic section above the Reyðarfjörður central volcano up to the Thingmuli central volcano, mapped by the British geologist G. P. L. Walker and his students in the 1950s and 60s. The groups were chosen as representative of the three predominant basalt types in Iceland, namely the Hólmar and Grjótá olivine basalt groups, the Kumlafell, Hólmatindur and Hjálmadalur aphyric basalt groups (mostly tholeiitic) and the Grænavatn porphyritic basalt group. Ground mapping and aerial photogrammetry were applied to assess the facies architecture of the groups, map their extent and distribution, measure the thickness of the lava flows and log the internal structure of representative flows. The source origin of each group was identified and the mode of emplacement of the flow types assessed with constraints on effusion rates. A new tectono-magmatic model for scale, geometry and evolution of the Neogene rift systems and mantle anomaly in Iceland is put forward, building on structural volcanological and geochemical evidence. Í jarðlagastafla Austfjarða eru mjög víðáttumiklar hraunlagasyrpur sem myndast hafa í miklum flæðigosum á míósen. Sex syrpur voru rannsakaðar en þær liggja í staflanum á milli megineldstöðva sem kenndar eru við Reyðarfjörð og Þingmúla. Syrpurnar endurspegla meginflokka íslenskra basalthrauna samkvæmt feltskiptingu G. P. L. Walkers, sem kortlagði þær ásamt samstarfsmönnum sínum upp úr miðri síðustu öld. Hólmasyrpa og Grjótársyrpa eru úr ólivínbasalti, Kumlafellssyrpa, Hólmatindssyrpa og Hjálmadalssyrpa að mestu úr dílalitlum hraunum af þóleiískri gerð en Grænavatnssyrpan að mestu úr dílabasalti. Uppbygging hraunlagasyrpanna var könnuð með nákvæmri loftljósmyndun. Þá var innri gerð hraunlaganna athuguð og henni lýst með aðferðum eðlisrænnar eldfjallafræði og ... Doctoral or Postdoctoral Thesis Iceland Skemman (Iceland) Reyðarfjörður ENVELOPE(-13.933,-13.933,65.021,65.021) Grænavatn ENVELOPE(-18.706,-18.706,64.138,64.138) Hólmar ENVELOPE(-14.065,-14.065,65.040,65.040) Hólmatindur ENVELOPE(-14.060,-14.060,65.061,65.061) Kumlafell ENVELOPE(-13.925,-13.925,64.864,64.864) |
institution |
Open Polar |
collection |
Skemman (Iceland) |
op_collection_id |
ftskemman |
language |
English |
topic |
Doktorsritgerðir |
spellingShingle |
Doktorsritgerðir Birgir Vilhelm Óskarsson 1982- Volcanological studies of Neogene flood basalt groups in eastern Iceland |
topic_facet |
Doktorsritgerðir |
description |
Included in the supplementary files are seven photogrammetric panels and one geological map (1:100 000) of eastern Iceland. Flood basalt groups in the Neogene lava piles of eastern Iceland are subject to investigation. The groups form the stratigraphic section above the Reyðarfjörður central volcano up to the Thingmuli central volcano, mapped by the British geologist G. P. L. Walker and his students in the 1950s and 60s. The groups were chosen as representative of the three predominant basalt types in Iceland, namely the Hólmar and Grjótá olivine basalt groups, the Kumlafell, Hólmatindur and Hjálmadalur aphyric basalt groups (mostly tholeiitic) and the Grænavatn porphyritic basalt group. Ground mapping and aerial photogrammetry were applied to assess the facies architecture of the groups, map their extent and distribution, measure the thickness of the lava flows and log the internal structure of representative flows. The source origin of each group was identified and the mode of emplacement of the flow types assessed with constraints on effusion rates. A new tectono-magmatic model for scale, geometry and evolution of the Neogene rift systems and mantle anomaly in Iceland is put forward, building on structural volcanological and geochemical evidence. Í jarðlagastafla Austfjarða eru mjög víðáttumiklar hraunlagasyrpur sem myndast hafa í miklum flæðigosum á míósen. Sex syrpur voru rannsakaðar en þær liggja í staflanum á milli megineldstöðva sem kenndar eru við Reyðarfjörð og Þingmúla. Syrpurnar endurspegla meginflokka íslenskra basalthrauna samkvæmt feltskiptingu G. P. L. Walkers, sem kortlagði þær ásamt samstarfsmönnum sínum upp úr miðri síðustu öld. Hólmasyrpa og Grjótársyrpa eru úr ólivínbasalti, Kumlafellssyrpa, Hólmatindssyrpa og Hjálmadalssyrpa að mestu úr dílalitlum hraunum af þóleiískri gerð en Grænavatnssyrpan að mestu úr dílabasalti. Uppbygging hraunlagasyrpanna var könnuð með nákvæmri loftljósmyndun. Þá var innri gerð hraunlaganna athuguð og henni lýst með aðferðum eðlisrænnar eldfjallafræði og ... |
author2 |
Háskóli Íslands |
format |
Doctoral or Postdoctoral Thesis |
author |
Birgir Vilhelm Óskarsson 1982- |
author_facet |
Birgir Vilhelm Óskarsson 1982- |
author_sort |
Birgir Vilhelm Óskarsson 1982- |
title |
Volcanological studies of Neogene flood basalt groups in eastern Iceland |
title_short |
Volcanological studies of Neogene flood basalt groups in eastern Iceland |
title_full |
Volcanological studies of Neogene flood basalt groups in eastern Iceland |
title_fullStr |
Volcanological studies of Neogene flood basalt groups in eastern Iceland |
title_full_unstemmed |
Volcanological studies of Neogene flood basalt groups in eastern Iceland |
title_sort |
volcanological studies of neogene flood basalt groups in eastern iceland |
publishDate |
2015 |
url |
http://hdl.handle.net/1946/22929 |
long_lat |
ENVELOPE(-13.933,-13.933,65.021,65.021) ENVELOPE(-18.706,-18.706,64.138,64.138) ENVELOPE(-14.065,-14.065,65.040,65.040) ENVELOPE(-14.060,-14.060,65.061,65.061) ENVELOPE(-13.925,-13.925,64.864,64.864) |
geographic |
Reyðarfjörður Grænavatn Hólmar Hólmatindur Kumlafell |
geographic_facet |
Reyðarfjörður Grænavatn Hólmar Hólmatindur Kumlafell |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
http://hdl.handle.net/1946/22929 |
_version_ |
1766036503435149312 |