A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan

Rhyolite and dacite lavas of the Mesoproterozoic upper Gawler Range Volcanics (GRV) (>30 000 km<sup>3</sup> preserved), South Australia, represent the remnants of one of the most voluminous felsic magmatic events preserved on Earth. Geophysical interpretation sugge...

Full description

Bibliographic Details
Main Authors: M. J. Pankhurst, B. F. Schaefer, P. G. Betts, N. Phillips, M. Hand
Format: Article
Language:English
Published: Copernicus Publications 2011-03-01
Series:Solid Earth
Online Access:http://www.solid-earth.net/2/25/2011/se-2-25-2011.pdf
_version_ 1811197372966895616
author M. J. Pankhurst
B. F. Schaefer
P. G. Betts
N. Phillips
M. Hand
author_facet M. J. Pankhurst
B. F. Schaefer
P. G. Betts
N. Phillips
M. Hand
author_sort M. J. Pankhurst
collection DOAJ
description Rhyolite and dacite lavas of the Mesoproterozoic upper Gawler Range Volcanics (GRV) (>30 000 km<sup>3</sup> preserved), South Australia, represent the remnants of one of the most voluminous felsic magmatic events preserved on Earth. Geophysical interpretation suggests eruption from a central cluster of feeder vents which supplied large-scale lobate flows >100 km in length. Pigeonite inversion thermometers indicate eruption temperatures of 950–1100 °C. The lavas are A-type in composition (e.g. high Ga/Al ratios) and characterised by elevated primary halogen concentrations (~1600 ppm fluorine, ~400 ppm chlorine). These depolymerised the magma such that temperature-composition-volatile non-Arrhenian melt viscosity modelling suggests they had viscosities of <3.5 log η (Pa s). These physicochemical properties have led to the emplacement of a Large Rhyolite Province, which has affinities in emplacement style to Large Basaltic Provinces. The low viscosity of these felsic magmas has produced a unique igneous system on a scale which is either not present or poorly preserved elsewhere on the planet. The Gawler Range Volcanic Province represents the erupted portion of the felsic end member of the family of voluminous, rapidly emplaced terrestrial magmatic provinces.
first_indexed 2024-04-12T01:12:15Z
format Article
id doaj.art-9900d4cbb1dd4823896e228d79a17a8c
institution Directory Open Access Journal
issn 1869-9510
1869-9529
language English
last_indexed 2024-04-12T01:12:15Z
publishDate 2011-03-01
publisher Copernicus Publications
record_format Article
series Solid Earth
spelling doaj.art-9900d4cbb1dd4823896e228d79a17a8c2022-12-22T03:54:03ZengCopernicus PublicationsSolid Earth1869-95101869-95292011-03-0121253310.5194/se-2-25-2011A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clanM. J. PankhurstB. F. SchaeferP. G. BettsN. PhillipsM. HandRhyolite and dacite lavas of the Mesoproterozoic upper Gawler Range Volcanics (GRV) (>30 000 km<sup>3</sup> preserved), South Australia, represent the remnants of one of the most voluminous felsic magmatic events preserved on Earth. Geophysical interpretation suggests eruption from a central cluster of feeder vents which supplied large-scale lobate flows >100 km in length. Pigeonite inversion thermometers indicate eruption temperatures of 950–1100 °C. The lavas are A-type in composition (e.g. high Ga/Al ratios) and characterised by elevated primary halogen concentrations (~1600 ppm fluorine, ~400 ppm chlorine). These depolymerised the magma such that temperature-composition-volatile non-Arrhenian melt viscosity modelling suggests they had viscosities of <3.5 log η (Pa s). These physicochemical properties have led to the emplacement of a Large Rhyolite Province, which has affinities in emplacement style to Large Basaltic Provinces. The low viscosity of these felsic magmas has produced a unique igneous system on a scale which is either not present or poorly preserved elsewhere on the planet. The Gawler Range Volcanic Province represents the erupted portion of the felsic end member of the family of voluminous, rapidly emplaced terrestrial magmatic provinces.http://www.solid-earth.net/2/25/2011/se-2-25-2011.pdf
spellingShingle M. J. Pankhurst
B. F. Schaefer
P. G. Betts
N. Phillips
M. Hand
A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
Solid Earth
title A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
title_full A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
title_fullStr A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
title_full_unstemmed A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
title_short A Mesoproterozoic continental flood rhyolite province, the Gawler Ranges, Australia: the end member example of the Large Igneous Province clan
title_sort mesoproterozoic continental flood rhyolite province the gawler ranges australia the end member example of the large igneous province clan
url http://www.solid-earth.net/2/25/2011/se-2-25-2011.pdf
work_keys_str_mv AT mjpankhurst amesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT bfschaefer amesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT pgbetts amesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT nphillips amesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT mhand amesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT mjpankhurst mesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT bfschaefer mesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT pgbetts mesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT nphillips mesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan
AT mhand mesoproterozoiccontinentalfloodrhyoliteprovincethegawlerrangesaustraliatheendmemberexampleofthelargeigneousprovinceclan