Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables
The dynamic and melting processes of a ridge-centred plume have been investigated in a companion paper by Ruedas et al. (hereafter referred to as Paper I) in a set of 3-D numerical fluid dynamic models with varying plume excess temperatures and melt extraction thresholds. In Paper I, the modelled th...
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fthighwire:oai:open-archive.highwire.org:gji:159/3/1097 2023-05-15T16:49:37+02:00 Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables Kreutzmann, A. Schmeling, H. Junge, A. Ruedas, T. Marquart, G. Bjarnason, I. Th. 2004-12-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/159/3/1097 https://doi.org/10.1111/j.1365-246X.2004.02397.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/159/3/1097 http://dx.doi.org/10.1111/j.1365-246X.2004.02397.x Copyright (C) 2004, Oxford University Press Tectonics and geodynamics TEXT 2004 fthighwire https://doi.org/10.1111/j.1365-246X.2004.02397.x 2013-05-26T17:39:56Z The dynamic and melting processes of a ridge-centred plume have been investigated in a companion paper by Ruedas et al. (hereafter referred to as Paper I) in a set of 3-D numerical fluid dynamic models with varying plume excess temperatures and melt extraction thresholds. In Paper I, the modelled thickness of the generated crust has been compared to observations of the Icelandic crust. Using the results of those plume models magnetotelluric (MT) transfer functions and seismic velocity anomalies are predicted in this paper. Together with Paper I, a dynamically consistent set of geophysical observables of a ridge-centred plume is presented and applied to Iceland. Temperature, partial melting and the connectivity of the melt phase influence the electrical conductivity of crust and mantle rocks. The temperature and melt fraction of our plume models are used to calculate 3-D conductivity models for MT modelling. For the melt geometry ellipsoidal inclusions with appropriate aspect ratios were assumed to control melt connectivity. The resulting transfer functions are compared to each other and to models not including a plume to separate signals from the ridge and the plume. They may be applied to observed MT measurements. If the plume head contains only 1 per cent of melt, the plume signal cannot be distinguished from the ridge signal, at least 3 per cent melt is needed for such distinction. The other predicted observables calculated from the different numerical models are seismic velocity anomalies. The temperature-induced V P and V S anomalies were estimated including anharmonic and anelastic effects as well as the water induced increase of dislocation mobility that lowers seismic velocities. Realistic melt geometries, as observed in laboratory experiments, were used to calculate the effect of partial melts on the seismic velocities. V S anomaly distributions are synthesized from the different plume models and compared to seismic observations. To reconcile seismic anomalies of the plume head and plume stem, a wet ... Text Iceland HighWire Press (Stanford University) Geophysical Journal International 159 3 1097 1111 |
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HighWire Press (Stanford University) |
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English |
topic |
Tectonics and geodynamics |
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Tectonics and geodynamics Kreutzmann, A. Schmeling, H. Junge, A. Ruedas, T. Marquart, G. Bjarnason, I. Th. Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables |
topic_facet |
Tectonics and geodynamics |
description |
The dynamic and melting processes of a ridge-centred plume have been investigated in a companion paper by Ruedas et al. (hereafter referred to as Paper I) in a set of 3-D numerical fluid dynamic models with varying plume excess temperatures and melt extraction thresholds. In Paper I, the modelled thickness of the generated crust has been compared to observations of the Icelandic crust. Using the results of those plume models magnetotelluric (MT) transfer functions and seismic velocity anomalies are predicted in this paper. Together with Paper I, a dynamically consistent set of geophysical observables of a ridge-centred plume is presented and applied to Iceland. Temperature, partial melting and the connectivity of the melt phase influence the electrical conductivity of crust and mantle rocks. The temperature and melt fraction of our plume models are used to calculate 3-D conductivity models for MT modelling. For the melt geometry ellipsoidal inclusions with appropriate aspect ratios were assumed to control melt connectivity. The resulting transfer functions are compared to each other and to models not including a plume to separate signals from the ridge and the plume. They may be applied to observed MT measurements. If the plume head contains only 1 per cent of melt, the plume signal cannot be distinguished from the ridge signal, at least 3 per cent melt is needed for such distinction. The other predicted observables calculated from the different numerical models are seismic velocity anomalies. The temperature-induced V P and V S anomalies were estimated including anharmonic and anelastic effects as well as the water induced increase of dislocation mobility that lowers seismic velocities. Realistic melt geometries, as observed in laboratory experiments, were used to calculate the effect of partial melts on the seismic velocities. V S anomaly distributions are synthesized from the different plume models and compared to seismic observations. To reconcile seismic anomalies of the plume head and plume stem, a wet ... |
format |
Text |
author |
Kreutzmann, A. Schmeling, H. Junge, A. Ruedas, T. Marquart, G. Bjarnason, I. Th. |
author_facet |
Kreutzmann, A. Schmeling, H. Junge, A. Ruedas, T. Marquart, G. Bjarnason, I. Th. |
author_sort |
Kreutzmann, A. |
title |
Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables |
title_short |
Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables |
title_full |
Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables |
title_fullStr |
Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables |
title_full_unstemmed |
Temperature and melting of a ridge-centred plume with application to Iceland. Part II: Predictions for electromagnetic and seismic observables |
title_sort |
temperature and melting of a ridge-centred plume with application to iceland. part ii: predictions for electromagnetic and seismic observables |
publisher |
Oxford University Press |
publishDate |
2004 |
url |
http://gji.oxfordjournals.org/cgi/content/short/159/3/1097 https://doi.org/10.1111/j.1365-246X.2004.02397.x |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/159/3/1097 http://dx.doi.org/10.1111/j.1365-246X.2004.02397.x |
op_rights |
Copyright (C) 2004, Oxford University Press |
op_doi |
https://doi.org/10.1111/j.1365-246X.2004.02397.x |
container_title |
Geophysical Journal International |
container_volume |
159 |
container_issue |
3 |
container_start_page |
1097 |
op_container_end_page |
1111 |
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1766039755466735616 |