Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production
In this study and a companion paper, numerical models of convection and melt generation in a ridge-centred plume system are developed for plumes with different temperature anomalies ? T P and varying fractions of retained melt ? ex . The produced melt in excess of the retention threshold is used to...
Published in: | Geophysical Journal International |
---|---|
Main Authors: | , , , , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2004
|
Subjects: | |
Online Access: | http://gji.oxfordjournals.org/cgi/content/short/158/2/729 https://doi.org/10.1111/j.1365-246X.2004.02311.x |
id |
fthighwire:oai:open-archive.highwire.org:gji:158/2/729 |
---|---|
record_format |
openpolar |
spelling |
fthighwire:oai:open-archive.highwire.org:gji:158/2/729 2023-05-15T16:47:03+02:00 Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production Ruedas, T. Schmeling, H. Marquart, G. Kreutzmann, A. Junge, A. 2004-08-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/158/2/729 https://doi.org/10.1111/j.1365-246X.2004.02311.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/158/2/729 http://dx.doi.org/10.1111/j.1365-246X.2004.02311.x Copyright (C) 2004, Oxford University Press Tectonics and Geodynamics TEXT 2004 fthighwire https://doi.org/10.1111/j.1365-246X.2004.02311.x 2013-05-26T18:00:39Z In this study and a companion paper, numerical models of convection and melt generation in a ridge-centred plume system are developed for plumes with different temperature anomalies ? T P and varying fractions of retained melt ? ex . The produced melt in excess of the retention threshold is used to generate ridge and plume crust respectively, whose thickness is found to be sensitive to changes in ? T P and ? ex . Comparison of calculated crustal thicknesses with observations from mid-oceanic ridges and from Iceland confirms earlier findings that ? T P of the Iceland plume in the upper mantle is about 150-200 K and that the Icelandic crust is thick. It also suggests that the retained melt fraction in partially molten mantle is at most 1 per cent. In the preferred model, plume melting occurs between ca. 25 and 110 km depth, at up to ~250 km from the spreading centre. The temperature and melt fraction fields from the numerical models are used as input for the derivation of seismic velocity anomalies and magnetotelluric response functions in the companion paper. Furthermore, the models reveal that the high temperatures of plumes result in a superlinear increase of crustal thickness with plume excess temperature through the combined effects of enhanced melting, active upwelling and the extent and geometry of the melting zone. Text Iceland HighWire Press (Stanford University) Geophysical Journal International 158 2 729 743 |
institution |
Open Polar |
collection |
HighWire Press (Stanford University) |
op_collection_id |
fthighwire |
language |
English |
topic |
Tectonics and Geodynamics |
spellingShingle |
Tectonics and Geodynamics Ruedas, T. Schmeling, H. Marquart, G. Kreutzmann, A. Junge, A. Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production |
topic_facet |
Tectonics and Geodynamics |
description |
In this study and a companion paper, numerical models of convection and melt generation in a ridge-centred plume system are developed for plumes with different temperature anomalies ? T P and varying fractions of retained melt ? ex . The produced melt in excess of the retention threshold is used to generate ridge and plume crust respectively, whose thickness is found to be sensitive to changes in ? T P and ? ex . Comparison of calculated crustal thicknesses with observations from mid-oceanic ridges and from Iceland confirms earlier findings that ? T P of the Iceland plume in the upper mantle is about 150-200 K and that the Icelandic crust is thick. It also suggests that the retained melt fraction in partially molten mantle is at most 1 per cent. In the preferred model, plume melting occurs between ca. 25 and 110 km depth, at up to ~250 km from the spreading centre. The temperature and melt fraction fields from the numerical models are used as input for the derivation of seismic velocity anomalies and magnetotelluric response functions in the companion paper. Furthermore, the models reveal that the high temperatures of plumes result in a superlinear increase of crustal thickness with plume excess temperature through the combined effects of enhanced melting, active upwelling and the extent and geometry of the melting zone. |
format |
Text |
author |
Ruedas, T. Schmeling, H. Marquart, G. Kreutzmann, A. Junge, A. |
author_facet |
Ruedas, T. Schmeling, H. Marquart, G. Kreutzmann, A. Junge, A. |
author_sort |
Ruedas, T. |
title |
Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production |
title_short |
Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production |
title_full |
Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production |
title_fullStr |
Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production |
title_full_unstemmed |
Temperature and melting of a ridge-centred plume with application to Iceland. Part I: Dynamics and crust production |
title_sort |
temperature and melting of a ridge-centred plume with application to iceland. part i: dynamics and crust production |
publisher |
Oxford University Press |
publishDate |
2004 |
url |
http://gji.oxfordjournals.org/cgi/content/short/158/2/729 https://doi.org/10.1111/j.1365-246X.2004.02311.x |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/158/2/729 http://dx.doi.org/10.1111/j.1365-246X.2004.02311.x |
op_rights |
Copyright (C) 2004, Oxford University Press |
op_doi |
https://doi.org/10.1111/j.1365-246X.2004.02311.x |
container_title |
Geophysical Journal International |
container_volume |
158 |
container_issue |
2 |
container_start_page |
729 |
op_container_end_page |
743 |
_version_ |
1766037146049708032 |