Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion
Udgivelsesdato: NOV 2005 Silicate liquid immiscibility in basalt petrogenesis is a contentious issue. Immiscible iron and silica-rich liquids were reported in melt inclusions of lunar basalt and in groundmass glasses of terrestrial volcanics. In fully crystallized plutonic rocks, however, silicate l...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2005
|
Subjects: | |
Online Access: | https://pure.au.dk/portal/da/publications/immiscible-iron-and-silicarich-melt-in-basalt-petrogenesis-documented-in-the-skaergaard-intrusion(3acea450-b1f0-11db-bee9-02004c4f4f50).html |
id |
ftuniaarhuspubl:oai:pure.atira.dk:publications/3acea450-b1f0-11db-bee9-02004c4f4f50 |
---|---|
record_format |
openpolar |
spelling |
ftuniaarhuspubl:oai:pure.atira.dk:publications/3acea450-b1f0-11db-bee9-02004c4f4f50 2023-05-15T16:03:50+02:00 Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion Jakobsen, Jakob Kløve Veksler, Ilya Tegner, Christian Brooks, C.Kent 2005 https://pure.au.dk/portal/da/publications/immiscible-iron-and-silicarich-melt-in-basalt-petrogenesis-documented-in-the-skaergaard-intrusion(3acea450-b1f0-11db-bee9-02004c4f4f50).html eng eng info:eu-repo/semantics/restrictedAccess Jakobsen , J K , Veksler , I , Tegner , C & Brooks , C K 2005 , ' Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion ' , Geology , vol. 33 , no. 11 , pp. 885-888 . article 2005 ftuniaarhuspubl 2020-08-05T22:41:50Z Udgivelsesdato: NOV 2005 Silicate liquid immiscibility in basalt petrogenesis is a contentious issue. Immiscible iron and silica-rich liquids were reported in melt inclusions of lunar basalt and in groundmass glasses of terrestrial volcanics. In fully crystallized plutonic rocks, however, silicate liquid immiscibility has yet to be proven. Here we report the first finding of natural, immiscible iron- and silica-rich melts in a plutonic environment documented in the Skaergaard intrusion, East Greenland. Primary melt inclusions (now finely crystallized) in apatite are either dark or light colored. The predominant dark colored type contains 30.9 6 4.2 wt% FeOt and 40.7 6 3.6 wt% SiO2, whereas the light colored type contains 8.6 6 5.9 wt% FeOt and 65.6 6 7.3 wt% SiO2. Similar light colored melt inclusions in olivine and fine grained dark and light colored interstitial pockets also give evidence of crystallization from emulsion of silica and iron-rich liquids. On the outcrop scale, silica-rich (melanogranophyre) pods and layers in iron-rich ferrodiorite of the Upper Zone of the Skaergaard intrusion witness segregation of the two liquids. These findings demand that silicate immiscibility is considered in basalt petrogenesis. Some granitic rocks may represent unmixed silica-rich melt, whereas the dense, iron-rich melt is likely to sink in the crust and could mix with hot mantle-derived magma to form unusual rocks, like ferropicrites, otherwise interpreted as products of heterogeneous mantle sources. Article in Journal/Newspaper East Greenland Greenland Aarhus University: Research Greenland |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
description |
Udgivelsesdato: NOV 2005 Silicate liquid immiscibility in basalt petrogenesis is a contentious issue. Immiscible iron and silica-rich liquids were reported in melt inclusions of lunar basalt and in groundmass glasses of terrestrial volcanics. In fully crystallized plutonic rocks, however, silicate liquid immiscibility has yet to be proven. Here we report the first finding of natural, immiscible iron- and silica-rich melts in a plutonic environment documented in the Skaergaard intrusion, East Greenland. Primary melt inclusions (now finely crystallized) in apatite are either dark or light colored. The predominant dark colored type contains 30.9 6 4.2 wt% FeOt and 40.7 6 3.6 wt% SiO2, whereas the light colored type contains 8.6 6 5.9 wt% FeOt and 65.6 6 7.3 wt% SiO2. Similar light colored melt inclusions in olivine and fine grained dark and light colored interstitial pockets also give evidence of crystallization from emulsion of silica and iron-rich liquids. On the outcrop scale, silica-rich (melanogranophyre) pods and layers in iron-rich ferrodiorite of the Upper Zone of the Skaergaard intrusion witness segregation of the two liquids. These findings demand that silicate immiscibility is considered in basalt petrogenesis. Some granitic rocks may represent unmixed silica-rich melt, whereas the dense, iron-rich melt is likely to sink in the crust and could mix with hot mantle-derived magma to form unusual rocks, like ferropicrites, otherwise interpreted as products of heterogeneous mantle sources. |
format |
Article in Journal/Newspaper |
author |
Jakobsen, Jakob Kløve Veksler, Ilya Tegner, Christian Brooks, C.Kent |
spellingShingle |
Jakobsen, Jakob Kløve Veksler, Ilya Tegner, Christian Brooks, C.Kent Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion |
author_facet |
Jakobsen, Jakob Kløve Veksler, Ilya Tegner, Christian Brooks, C.Kent |
author_sort |
Jakobsen, Jakob Kløve |
title |
Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion |
title_short |
Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion |
title_full |
Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion |
title_fullStr |
Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion |
title_full_unstemmed |
Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion |
title_sort |
immiscible iron- and silica-rich melt in basalt petrogenesis documented in the skaergaard intrusion |
publishDate |
2005 |
url |
https://pure.au.dk/portal/da/publications/immiscible-iron-and-silicarich-melt-in-basalt-petrogenesis-documented-in-the-skaergaard-intrusion(3acea450-b1f0-11db-bee9-02004c4f4f50).html |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
East Greenland Greenland |
genre_facet |
East Greenland Greenland |
op_source |
Jakobsen , J K , Veksler , I , Tegner , C & Brooks , C K 2005 , ' Immiscible iron- and silica-rich melt in basalt petrogenesis documented in the Skaergaard intrusion ' , Geology , vol. 33 , no. 11 , pp. 885-888 . |
op_rights |
info:eu-repo/semantics/restrictedAccess |
_version_ |
1766399527487537152 |