Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing
In southern Iceland, tholeiitic basalt magmas propagating laterally from the active Eastern Rift Zone into the older cmstal segment of the South Eastern Zone have been injected into Torfaj�kull, a mature volcanic centre dominated by rhyolites. Eruptions of complex suites of mixed and hybrid rocks ha...
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fthighwire:oai:open-archive.highwire.org:petrology:31/2/461 2023-05-15T16:47:36+02:00 Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing McGARVIE, D. W. MACDONALD, R. PINKERTON, H. SMITH, R. L. 1990-04-01 00:00:00.0 text/html http://petrology.oxfordjournals.org/cgi/content/short/31/2/461 https://doi.org/10.1093/petrology/31.2.461 en eng Oxford University Press http://petrology.oxfordjournals.org/cgi/content/short/31/2/461 http://dx.doi.org/10.1093/petrology/31.2.461 Copyright (C) 1990, Oxford University Press Articles TEXT 1990 fthighwire https://doi.org/10.1093/petrology/31.2.461 2013-05-26T23:10:18Z In southern Iceland, tholeiitic basalt magmas propagating laterally from the active Eastern Rift Zone into the older cmstal segment of the South Eastern Zone have been injected into Torfaj�kull, a mature volcanic centre dominated by rhyolites. Eruptions of complex suites of mixed and hybrid rocks have been triggered, involving tholeiites of the rift zone and transitional basalts and rhyolites of the Torfaj�kull centre. Three-component hybrids are an unusual feature of the activity. The distribution of various magma mixing and hybrid types is related to the periodic injection of tholeiite into a magma chamber, or chambers, where rhyolite overlies parental transitional basalts. Pre-postglacial rhyolites (>10000 y) at Torfajokull are predominantly peralkaline, whereas later rhyolites are, with few exceptions, subalkaline. Furthermore, the injection of rift zone magmas, and the consequent abundance of rhyolite-basalt mixing, have been important features of magmatism at the centre only in postglacial times. Reduced repose times in the magma reservoirs have prevented the production of peralkaline rhyolites. These trends are interpreted in terms of the southerly migration of the Eastern Rift Zone. Text Iceland HighWire Press (Stanford University) Torfajökull ENVELOPE(-19.027,-19.027,63.898,63.898) Journal of Petrology 31 2 461 481 |
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English |
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Articles |
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Articles McGARVIE, D. W. MACDONALD, R. PINKERTON, H. SMITH, R. L. Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing |
topic_facet |
Articles |
description |
In southern Iceland, tholeiitic basalt magmas propagating laterally from the active Eastern Rift Zone into the older cmstal segment of the South Eastern Zone have been injected into Torfaj�kull, a mature volcanic centre dominated by rhyolites. Eruptions of complex suites of mixed and hybrid rocks have been triggered, involving tholeiites of the rift zone and transitional basalts and rhyolites of the Torfaj�kull centre. Three-component hybrids are an unusual feature of the activity. The distribution of various magma mixing and hybrid types is related to the periodic injection of tholeiite into a magma chamber, or chambers, where rhyolite overlies parental transitional basalts. Pre-postglacial rhyolites (>10000 y) at Torfajokull are predominantly peralkaline, whereas later rhyolites are, with few exceptions, subalkaline. Furthermore, the injection of rift zone magmas, and the consequent abundance of rhyolite-basalt mixing, have been important features of magmatism at the centre only in postglacial times. Reduced repose times in the magma reservoirs have prevented the production of peralkaline rhyolites. These trends are interpreted in terms of the southerly migration of the Eastern Rift Zone. |
format |
Text |
author |
McGARVIE, D. W. MACDONALD, R. PINKERTON, H. SMITH, R. L. |
author_facet |
McGARVIE, D. W. MACDONALD, R. PINKERTON, H. SMITH, R. L. |
author_sort |
McGARVIE, D. W. |
title |
Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing |
title_short |
Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing |
title_full |
Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing |
title_fullStr |
Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing |
title_full_unstemmed |
Petrogenetic Evolution of the Torfajökull Volcanic Complex, Iceland II. The Role of Magma Mixing |
title_sort |
petrogenetic evolution of the torfajökull volcanic complex, iceland ii. the role of magma mixing |
publisher |
Oxford University Press |
publishDate |
1990 |
url |
http://petrology.oxfordjournals.org/cgi/content/short/31/2/461 https://doi.org/10.1093/petrology/31.2.461 |
long_lat |
ENVELOPE(-19.027,-19.027,63.898,63.898) |
geographic |
Torfajökull |
geographic_facet |
Torfajökull |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
http://petrology.oxfordjournals.org/cgi/content/short/31/2/461 http://dx.doi.org/10.1093/petrology/31.2.461 |
op_rights |
Copyright (C) 1990, Oxford University Press |
op_doi |
https://doi.org/10.1093/petrology/31.2.461 |
container_title |
Journal of Petrology |
container_volume |
31 |
container_issue |
2 |
container_start_page |
461 |
op_container_end_page |
481 |
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1766037692378775552 |