Stratigraphy-related, low-pressure metamorphism in the Hardey Syncline, Hamersley Province, Western Australia

Takazo Shibuya, Kazumasa Aoki, Tsuyoshi Komiya, Shigenori Maruyama

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The late Archean Fortescue Group and Paleoproterozoic Hamersley Group are exposed in the Hardey Syncline located at the southwestern edge of the Hamersley Basin, Pilbara Craton, Western Australia. The secondary mineral assemblages and compositions of the basaltic rocks of the Fortescue and Hamersley Groups reveal the metamorphic conditions of the study area. The estimated metamorphic grade ranges from prehnite-actinolite facies (Hamersley Group), through greenschist facies (Fortescue Group), to a transition between greenschist facies and actinolite-calcic plagioclase facies (Fortescue Group), indicating a low-pressure type metamorphic facies series. The metamorphic grade increases northward, which is opposite to the general southward increase of the regional metamorphic grade. Furthermore, the change of metamorphic grade strongly correlates with stratigraphy, and the metamorphic temperature increases with stratigraphic depth. These observations suggest that the metamorphism of the study area was caused by a thermal event before the folding due to the Ophthalmian orogeny that affected most of the Hamersley Province. Considering the presence of 2.2 Ga dolerite sills in the Hardey Syncline and the low-pressure metamorphic condition, it is suggested that the metamorphism of the study area was caused by the 2.2 Ga continental rifting, which is consistent with the reported metamorphic age.

Original languageEnglish
Pages (from-to)213-221
Number of pages9
JournalGondwana Research
Volume18
Issue number1
DOIs
Publication statusPublished - Jul 2010
Externally publishedYes

Fingerprint

syncline
greenschist facies
low pressure
metamorphism
stratigraphy
metamorphic facies
prehnite
secondary mineral
diabase
sill
orogeny
rifting
folding
craton
Archean
plagioclase
basin
rock
temperature
province

Keywords

  • Continental rifting
  • Hamersley Province
  • Low-pressure metamorphism
  • Ophthalmian orogeny
  • Paleoproterozoic
  • Tectonics

ASJC Scopus subject areas

  • Geology

Cite this

Stratigraphy-related, low-pressure metamorphism in the Hardey Syncline, Hamersley Province, Western Australia. / Shibuya, Takazo; Aoki, Kazumasa; Komiya, Tsuyoshi; Maruyama, Shigenori.

In: Gondwana Research, Vol. 18, No. 1, 07.2010, p. 213-221.

Research output: Contribution to journalArticle

Shibuya, Takazo ; Aoki, Kazumasa ; Komiya, Tsuyoshi ; Maruyama, Shigenori. / Stratigraphy-related, low-pressure metamorphism in the Hardey Syncline, Hamersley Province, Western Australia. In: Gondwana Research. 2010 ; Vol. 18, No. 1. pp. 213-221.
@article{19d8a4ed0fbd4f70bb15148bd8192122,
title = "Stratigraphy-related, low-pressure metamorphism in the Hardey Syncline, Hamersley Province, Western Australia",
abstract = "The late Archean Fortescue Group and Paleoproterozoic Hamersley Group are exposed in the Hardey Syncline located at the southwestern edge of the Hamersley Basin, Pilbara Craton, Western Australia. The secondary mineral assemblages and compositions of the basaltic rocks of the Fortescue and Hamersley Groups reveal the metamorphic conditions of the study area. The estimated metamorphic grade ranges from prehnite-actinolite facies (Hamersley Group), through greenschist facies (Fortescue Group), to a transition between greenschist facies and actinolite-calcic plagioclase facies (Fortescue Group), indicating a low-pressure type metamorphic facies series. The metamorphic grade increases northward, which is opposite to the general southward increase of the regional metamorphic grade. Furthermore, the change of metamorphic grade strongly correlates with stratigraphy, and the metamorphic temperature increases with stratigraphic depth. These observations suggest that the metamorphism of the study area was caused by a thermal event before the folding due to the Ophthalmian orogeny that affected most of the Hamersley Province. Considering the presence of 2.2 Ga dolerite sills in the Hardey Syncline and the low-pressure metamorphic condition, it is suggested that the metamorphism of the study area was caused by the 2.2 Ga continental rifting, which is consistent with the reported metamorphic age.",
keywords = "Continental rifting, Hamersley Province, Low-pressure metamorphism, Ophthalmian orogeny, Paleoproterozoic, Tectonics",
author = "Takazo Shibuya and Kazumasa Aoki and Tsuyoshi Komiya and Shigenori Maruyama",
year = "2010",
month = "7",
doi = "10.1016/j.gr.2010.01.002",
language = "English",
volume = "18",
pages = "213--221",
journal = "Gondwana Research",
issn = "1342-937X",
publisher = "Elsevier Inc.",
number = "1",

}

TY - JOUR

T1 - Stratigraphy-related, low-pressure metamorphism in the Hardey Syncline, Hamersley Province, Western Australia

AU - Shibuya, Takazo

AU - Aoki, Kazumasa

AU - Komiya, Tsuyoshi

AU - Maruyama, Shigenori

PY - 2010/7

Y1 - 2010/7

N2 - The late Archean Fortescue Group and Paleoproterozoic Hamersley Group are exposed in the Hardey Syncline located at the southwestern edge of the Hamersley Basin, Pilbara Craton, Western Australia. The secondary mineral assemblages and compositions of the basaltic rocks of the Fortescue and Hamersley Groups reveal the metamorphic conditions of the study area. The estimated metamorphic grade ranges from prehnite-actinolite facies (Hamersley Group), through greenschist facies (Fortescue Group), to a transition between greenschist facies and actinolite-calcic plagioclase facies (Fortescue Group), indicating a low-pressure type metamorphic facies series. The metamorphic grade increases northward, which is opposite to the general southward increase of the regional metamorphic grade. Furthermore, the change of metamorphic grade strongly correlates with stratigraphy, and the metamorphic temperature increases with stratigraphic depth. These observations suggest that the metamorphism of the study area was caused by a thermal event before the folding due to the Ophthalmian orogeny that affected most of the Hamersley Province. Considering the presence of 2.2 Ga dolerite sills in the Hardey Syncline and the low-pressure metamorphic condition, it is suggested that the metamorphism of the study area was caused by the 2.2 Ga continental rifting, which is consistent with the reported metamorphic age.

AB - The late Archean Fortescue Group and Paleoproterozoic Hamersley Group are exposed in the Hardey Syncline located at the southwestern edge of the Hamersley Basin, Pilbara Craton, Western Australia. The secondary mineral assemblages and compositions of the basaltic rocks of the Fortescue and Hamersley Groups reveal the metamorphic conditions of the study area. The estimated metamorphic grade ranges from prehnite-actinolite facies (Hamersley Group), through greenschist facies (Fortescue Group), to a transition between greenschist facies and actinolite-calcic plagioclase facies (Fortescue Group), indicating a low-pressure type metamorphic facies series. The metamorphic grade increases northward, which is opposite to the general southward increase of the regional metamorphic grade. Furthermore, the change of metamorphic grade strongly correlates with stratigraphy, and the metamorphic temperature increases with stratigraphic depth. These observations suggest that the metamorphism of the study area was caused by a thermal event before the folding due to the Ophthalmian orogeny that affected most of the Hamersley Province. Considering the presence of 2.2 Ga dolerite sills in the Hardey Syncline and the low-pressure metamorphic condition, it is suggested that the metamorphism of the study area was caused by the 2.2 Ga continental rifting, which is consistent with the reported metamorphic age.

KW - Continental rifting

KW - Hamersley Province

KW - Low-pressure metamorphism

KW - Ophthalmian orogeny

KW - Paleoproterozoic

KW - Tectonics

UR - http://www.scopus.com/inward/record.url?scp=77952431015&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77952431015&partnerID=8YFLogxK

U2 - 10.1016/j.gr.2010.01.002

DO - 10.1016/j.gr.2010.01.002

M3 - Article

AN - SCOPUS:77952431015

VL - 18

SP - 213

EP - 221

JO - Gondwana Research

JF - Gondwana Research

SN - 1342-937X

IS - 1

ER -