.Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting
A new collection of mantle xenoliths in Tertiary dykes from the Wiedemann Fjord area in Southeast Greenland shows that this part of the central Greenland craton is underlain by highly depleted peridotites. The samples are mostly spinel .harzburgites with highly forsteritic olivines Fo, average Fo. T...
Main Authors: | , , |
---|---|
Other Authors: | |
Format: | Text |
Language: | English |
Published: |
1997
|
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.487.9419 http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf |
id |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.487.9419 |
---|---|
record_format |
openpolar |
spelling |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.487.9419 2023-05-15T16:03:53+02:00 .Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting Stefan Bernstein A Peter B. Kelemen B C. Kent Brooks A The Pennsylvania State University CiteSeerX Archives 1997 application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.487.9419 http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.487.9419 http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf text 1997 ftciteseerx 2016-01-08T08:18:09Z A new collection of mantle xenoliths in Tertiary dykes from the Wiedemann Fjord area in Southeast Greenland shows that this part of the central Greenland craton is underlain by highly depleted peridotites. The samples are mostly spinel .harzburgites with highly forsteritic olivines Fo, average Fo. This, together with unusually high modal olivine87 – 94 92.7 .contents 70–)95 % , places the Wiedemann harzburgites in a unique compositional field. Relative to depleted Kaapvaal harzburgites with comparable Fo in olivine, the Wiedemann samples have considerably lower bulk SiO average 42.6 wt%2.versus 44–49 wt %. Spinel compositions are similar to those in other sub-cratonic harzburgites. Pyroxene equilibrium temperatures average 8508C, which is above an Archaean cratonic geotherm at an inferred pressure of 1–2 GPa, but low enough so that it is unlikely that the xenoliths represent residual peridotites created during Tertiary magmatism. Among mantle samples, the Wiedemann harzburgites are, in terms of their bulk composition, most similar to harzburgites from the . .ophiolites of Papua New Guinea PNG and New Caledonia NC. One hypothesis is that the Wiedemann harzburgites, along with PNG and NC harzburgites, formed via dissolution of pyroxene from previously depleted peridotites, possibly beneath a volcanic arc. If so, higher spinel CrrAl in Wiedemann samples may reflect a deeper origin compared to PNG and NC peridotites. Alternatively, using proposed primitive mantle compositions as a protolith, the Wiedemann harzburgites can be modeled as the residue after extraction of some 40 % melt. The composition of this calculated hypothetical melt in terms of CaO, Al O, FeO, MgO and SiO is similar to published experimental data on high degree melts of peridotite at 2–32 3 2 Text East Greenland Greenland Unknown Greenland Wiedemann Fjord ENVELOPE(-28.250,-28.250,68.483,68.483) |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
ftciteseerx |
language |
English |
description |
A new collection of mantle xenoliths in Tertiary dykes from the Wiedemann Fjord area in Southeast Greenland shows that this part of the central Greenland craton is underlain by highly depleted peridotites. The samples are mostly spinel .harzburgites with highly forsteritic olivines Fo, average Fo. This, together with unusually high modal olivine87 – 94 92.7 .contents 70–)95 % , places the Wiedemann harzburgites in a unique compositional field. Relative to depleted Kaapvaal harzburgites with comparable Fo in olivine, the Wiedemann samples have considerably lower bulk SiO average 42.6 wt%2.versus 44–49 wt %. Spinel compositions are similar to those in other sub-cratonic harzburgites. Pyroxene equilibrium temperatures average 8508C, which is above an Archaean cratonic geotherm at an inferred pressure of 1–2 GPa, but low enough so that it is unlikely that the xenoliths represent residual peridotites created during Tertiary magmatism. Among mantle samples, the Wiedemann harzburgites are, in terms of their bulk composition, most similar to harzburgites from the . .ophiolites of Papua New Guinea PNG and New Caledonia NC. One hypothesis is that the Wiedemann harzburgites, along with PNG and NC harzburgites, formed via dissolution of pyroxene from previously depleted peridotites, possibly beneath a volcanic arc. If so, higher spinel CrrAl in Wiedemann samples may reflect a deeper origin compared to PNG and NC peridotites. Alternatively, using proposed primitive mantle compositions as a protolith, the Wiedemann harzburgites can be modeled as the residue after extraction of some 40 % melt. The composition of this calculated hypothetical melt in terms of CaO, Al O, FeO, MgO and SiO is similar to published experimental data on high degree melts of peridotite at 2–32 3 2 |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Stefan Bernstein A Peter B. Kelemen B C. Kent Brooks A |
spellingShingle |
Stefan Bernstein A Peter B. Kelemen B C. Kent Brooks A .Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting |
author_facet |
Stefan Bernstein A Peter B. Kelemen B C. Kent Brooks A |
author_sort |
Stefan Bernstein A |
title |
.Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting |
title_short |
.Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting |
title_full |
.Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting |
title_fullStr |
.Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting |
title_full_unstemmed |
.Earth and Planetary Science Letters 154 1998 221–235 Depleted spinel harzburgite xenoliths in Tertiary dykes from East Greenland: Restites from high degree melting |
title_sort |
.earth and planetary science letters 154 1998 221–235 depleted spinel harzburgite xenoliths in tertiary dykes from east greenland: restites from high degree melting |
publishDate |
1997 |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.487.9419 http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf |
long_lat |
ENVELOPE(-28.250,-28.250,68.483,68.483) |
geographic |
Greenland Wiedemann Fjord |
geographic_facet |
Greenland Wiedemann Fjord |
genre |
East Greenland Greenland |
genre_facet |
East Greenland Greenland |
op_source |
http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.487.9419 http://science.whoi.edu/labs/mclean210/kelemen/pages/Bernstein et al xen EPSL 98.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766399580818112512 |