The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin
Vesteris Seamount is a solitary alkaline volcano in the Greenland Basin some 280 km NW of Jan Mayen. Topographic and geophysical studies have shown no sign of an associated plume trace. Evidence from ash layers in sediment cores around the volcano and dating of dredged samples show that it has been...
Published in: | Journal of Petrology |
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Language: | English |
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Oxford Univ. Press
1994
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Online Access: | https://oceanrep.geomar.de/id/eprint/8377/ https://oceanrep.geomar.de/id/eprint/8377/1/Haase_Devey.pdf https://doi.org/10.1093/petrology/35.2.295 |
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ftoceanrep:oai:oceanrep.geomar.de:8377 2023-05-15T16:27:45+02:00 The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin Haase, Karsten M. Devey, Colin W. 1994 text https://oceanrep.geomar.de/id/eprint/8377/ https://oceanrep.geomar.de/id/eprint/8377/1/Haase_Devey.pdf https://doi.org/10.1093/petrology/35.2.295 en eng Oxford Univ. Press https://oceanrep.geomar.de/id/eprint/8377/1/Haase_Devey.pdf Haase, K. M. and Devey, C. W. (1994) The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin. Journal of Petrology, 35 (2). pp. 295-328. DOI 10.1093/petrology/35.2.295 <https://doi.org/10.1093/petrology%2F35.2.295>. doi:10.1093/petrology/35.2.295 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 1994 ftoceanrep https://doi.org/10.1093/petrology/35.2.295 2023-04-07T14:56:37Z Vesteris Seamount is a solitary alkaline volcano in the Greenland Basin some 280 km NW of Jan Mayen. Topographic and geophysical studies have shown no sign of an associated plume trace. Evidence from ash layers in sediment cores around the volcano and dating of dredged samples show that it has been active in Quaternary times. The lavas from Vesteris studied here consist of basanites, tephrites, mugearite, and alkali basalts. Crystal fractionation models are consistent with the generation of the tephrites and mugearite from a basanitic parent. Extensive kaersutite fractionation is required late in the fractionation sequence to produce the extreme mugearite composition. Na-Al-Fe-rich green cores to many clinopyroxene phenocrysts at Vesteris suggest a fractionation history beginning at high pressure in the mantle. Differences between Vesteris and Jan Mayen in the ratios of highly incompatible trace elements such as Ce/Pb and Rb/Cs, which will not normally be fractionated from one another during mantle melting, suggest that the two are not derived from the same source. Relatively unradiogenic Sr isotope ratios (compared with Bulk Earth), and highly incompatible trace element patterns similar to those for St. Helena, suggest that Vesteris magmas are derived from a depleted, asthenospheric source. We propose that the Vesteris basanites are very low degree partial melts (˜1%) of this source, most probably those which give rise to the seismic low-velocity zone (LVZ). Such small-degree melts may preferentially tap small-scale heterogeneities in the asthenosphere. Vesteris lies at the intersection of two major structural trends in the Greenland Basin—(1) a zone of major reorientation of spreading direction on the Mohns Ridge north of Jan Mayen and (2) the extension of the Kolbeinsey Ridge axis. We propose that a combination of the extensional stress fields related to these two lineaments produces sufficient dilation of the lithosphere at Vesteris to allow magmas from the LVZ to reach the surface. Article in Journal/Newspaper Greenland Jan Mayen Kolbeinsey OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Greenland Greenland Basin ENVELOPE(-5.000,-5.000,73.500,73.500) Jan Mayen Kolbeinsey ENVELOPE(-18.687,-18.687,67.149,67.149) Kolbeinsey Ridge ENVELOPE(-16.917,-16.917,68.833,68.833) St. Helena ENVELOPE(8.575,8.575,63.621,63.621) Vesteris Seamount ENVELOPE(-9.113,-9.113,73.519,73.519) Journal of Petrology 35 2 295 328 |
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Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Vesteris Seamount is a solitary alkaline volcano in the Greenland Basin some 280 km NW of Jan Mayen. Topographic and geophysical studies have shown no sign of an associated plume trace. Evidence from ash layers in sediment cores around the volcano and dating of dredged samples show that it has been active in Quaternary times. The lavas from Vesteris studied here consist of basanites, tephrites, mugearite, and alkali basalts. Crystal fractionation models are consistent with the generation of the tephrites and mugearite from a basanitic parent. Extensive kaersutite fractionation is required late in the fractionation sequence to produce the extreme mugearite composition. Na-Al-Fe-rich green cores to many clinopyroxene phenocrysts at Vesteris suggest a fractionation history beginning at high pressure in the mantle. Differences between Vesteris and Jan Mayen in the ratios of highly incompatible trace elements such as Ce/Pb and Rb/Cs, which will not normally be fractionated from one another during mantle melting, suggest that the two are not derived from the same source. Relatively unradiogenic Sr isotope ratios (compared with Bulk Earth), and highly incompatible trace element patterns similar to those for St. Helena, suggest that Vesteris magmas are derived from a depleted, asthenospheric source. We propose that the Vesteris basanites are very low degree partial melts (˜1%) of this source, most probably those which give rise to the seismic low-velocity zone (LVZ). Such small-degree melts may preferentially tap small-scale heterogeneities in the asthenosphere. Vesteris lies at the intersection of two major structural trends in the Greenland Basin—(1) a zone of major reorientation of spreading direction on the Mohns Ridge north of Jan Mayen and (2) the extension of the Kolbeinsey Ridge axis. We propose that a combination of the extensional stress fields related to these two lineaments produces sufficient dilation of the lithosphere at Vesteris to allow magmas from the LVZ to reach the surface. |
format |
Article in Journal/Newspaper |
author |
Haase, Karsten M. Devey, Colin W. |
spellingShingle |
Haase, Karsten M. Devey, Colin W. The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin |
author_facet |
Haase, Karsten M. Devey, Colin W. |
author_sort |
Haase, Karsten M. |
title |
The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin |
title_short |
The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin |
title_full |
The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin |
title_fullStr |
The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin |
title_full_unstemmed |
The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin |
title_sort |
petrology and geochemistry of vesteris seamount, greenland basin - an intraplate alkaline volcano of non-plume origin |
publisher |
Oxford Univ. Press |
publishDate |
1994 |
url |
https://oceanrep.geomar.de/id/eprint/8377/ https://oceanrep.geomar.de/id/eprint/8377/1/Haase_Devey.pdf https://doi.org/10.1093/petrology/35.2.295 |
long_lat |
ENVELOPE(-5.000,-5.000,73.500,73.500) ENVELOPE(-18.687,-18.687,67.149,67.149) ENVELOPE(-16.917,-16.917,68.833,68.833) ENVELOPE(8.575,8.575,63.621,63.621) ENVELOPE(-9.113,-9.113,73.519,73.519) |
geographic |
Greenland Greenland Basin Jan Mayen Kolbeinsey Kolbeinsey Ridge St. Helena Vesteris Seamount |
geographic_facet |
Greenland Greenland Basin Jan Mayen Kolbeinsey Kolbeinsey Ridge St. Helena Vesteris Seamount |
genre |
Greenland Jan Mayen Kolbeinsey |
genre_facet |
Greenland Jan Mayen Kolbeinsey |
op_relation |
https://oceanrep.geomar.de/id/eprint/8377/1/Haase_Devey.pdf Haase, K. M. and Devey, C. W. (1994) The petrology and geochemistry of Vesteris Seamount, Greenland Basin - An intraplate alkaline volcano of non-plume origin. Journal of Petrology, 35 (2). pp. 295-328. DOI 10.1093/petrology/35.2.295 <https://doi.org/10.1093/petrology%2F35.2.295>. doi:10.1093/petrology/35.2.295 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1093/petrology/35.2.295 |
container_title |
Journal of Petrology |
container_volume |
35 |
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2 |
container_start_page |
295 |
op_container_end_page |
328 |
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1766017264316841984 |