Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Orogeny associated with anticlockwise P-T-t paths; evidence from low-P, high-T metamorphic terranes in the Arunta Inlier, central Australia

W. J. Collins and R. H. Vernon
Orogeny associated with anticlockwise P-T-t paths; evidence from low-P, high-T metamorphic terranes in the Arunta Inlier, central Australia
Geology (Boulder) (August 1991) 19 (8): 835-838

Abstract

Low-pressure, high-temperature metamorphic terranes from the Proterozoic northern Arunta inlier, central Australia, are characterized by anticlockwise pressure-temperature-time paths. The thermal peak was reached before or during the earliest folding, and it was associated with abundant, repeated intrusion of granite sheets. We generalize our observations in the area to infer that low- P, high-T metamorphism is induced principally by focusing of mid-crustal heat from rapid, repeated granite sheet intrusion, which generates large metamorphic aureoles. Intrusion and associated metamorphism produce melting reactions, which increase the fluid pressure and thermally soften the mid-crust, resulting in accelerated, melt-enhanced deformation. Shortening is accommodated generally by thrusting in the mid-crust and by upright folding in the upper crust. Compression occurs during cooling of the terrane, as indicated by near-isobaric cooling paths and the preservation of upper-crust sections. The result is the production of discrete low-P, high- T terranes that are localized around abundant granitoids, show thin-skinned deformation, and have anticlockwise P-T-time paths. Continued granitoid intrusion produces posttectonic, discordant plutons at high crustal levels, within low-P metamorphic belts.


ISSN: 0091-7613
EISSN: 1943-2682
Coden: GLGYBA
Serial Title: Geology (Boulder)
Serial Volume: 19
Serial Issue: 8
Title: Orogeny associated with anticlockwise P-T-t paths; evidence from low-P, high-T metamorphic terranes in the Arunta Inlier, central Australia
Affiliation: Univ. Newcastle, Dep. Geol., Newcastle, N.S.W., Australia
Pages: 835-838
Published: 199108
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
References: 27
Accession Number: 1991-040146
Categories: Structural geologyIgneous and metamorphic petrology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. sects., geol. sketch map
S26°00'00" - S11°00'00", E129°00'00" - E138°00'00"
Secondary Affiliation: Macquarie Univ., AUS, Australia
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute.
Update Code: 1991
Close Modal

or Create an Account

Close Modal
Close Modal