Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica
<jats:title>Abstract</jats:title><jats:p>Meta-sediments in the Larsemann Hills that preserve a coherent stratigraphy, form a cover sequence deposited upon basement of mafic–felsic granulite. Their outcrop pattern defines a 10 kilometre wide east–west trending synclinal trough struc...
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Cambridge University Press
1995
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Online Access: | http://hdl.handle.net/2440/13710 https://doi.org/10.1017/S0016756800011729 |
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ftunivadelaidedl:oai:digital.library.adelaide.edu.au:2440/13710 2023-05-15T13:43:19+02:00 Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica Carson, C. Dirks, P. Hand, M. Sims, J. Wilson, C. 1995 application/pdf http://hdl.handle.net/2440/13710 https://doi.org/10.1017/S0016756800011729 en eng Cambridge University Press Geological Magazine, 1995; 132(2):151-170 0016-7568 1469-5081 http://hdl.handle.net/2440/13710 doi:10.1017/S0016756800011729 Hand, M. [0000-0003-3743-9706] Copyright © Cambridge University Press 1995 Journal article 1995 ftunivadelaidedl https://doi.org/10.1017/S0016756800011729 2023-02-05T19:30:20Z <jats:title>Abstract</jats:title><jats:p>Meta-sediments in the Larsemann Hills that preserve a coherent stratigraphy, form a cover sequence deposited upon basement of mafic–felsic granulite. Their outcrop pattern defines a 10 kilometre wide east–west trending synclinal trough structure in which basement–cover contacts differ in the north and the south, suggesting tectonic interleaving during a prograde, D<jats:sub>1</jats:sub> thickening event. Subsequent conditions reached low-medium pressure granulite grade, and structures can be divided into two groups, D<jats:sub>2</jats:sub> and D<jats:sub>3</jats:sub>, each defined by a unique lineation direction and shear sense. D<jats:sub>2</jats:sub> structures which are associated with the dominant gneissic foliation in much of the Larsemann Hills, contain a moderately east-plunging lineation indicative of west-directed thrusting. D<jats:sub>2</jats:sub> comprises a colinear fold sequence that evolved from early intrafolial folds to late upright folds. D<jats:sub>3</jats:sub> structures are associated with a high-strain zone, to the south of the Larsemann Hills, where S<jats:sub>3</jats:sub> is the dominant gneissic layering and folds sequences resemble D<jats:sub>2</jats:sub> folding. Outside the D<jats:sub>3</jats:sub> high-strain zone occurs a low-strain D<jats:sub>3</jats:sub> window, preserving low-strain D<jats:sub>3</jats:sub> structures (minor shear bands and upright folds) that partly re-orient D<jats:sub>2</jats:sub> structures. All structures are truncated by a series of planar pegmatites and parallel D<jats:sub>4</jats:sub> mylonite zones, recording extensional dextral displacements.</jats:p><jats:p>D<jats:sub>2</jats:sub> assemblages include coexisting garnet–orthopyroxene pairs recording peak conditions of ∼ 7 kbar and ∼ 780°C. Subsequent retrograde ... Article in Journal/Newspaper Antarc* Antarctica East Antarctica The University of Adelaide: Digital Library East Antarctica Larsemann Hills ENVELOPE(76.217,76.217,-69.400,-69.400) Geological Magazine 132 2 151 170 |
institution |
Open Polar |
collection |
The University of Adelaide: Digital Library |
op_collection_id |
ftunivadelaidedl |
language |
English |
description |
<jats:title>Abstract</jats:title><jats:p>Meta-sediments in the Larsemann Hills that preserve a coherent stratigraphy, form a cover sequence deposited upon basement of mafic–felsic granulite. Their outcrop pattern defines a 10 kilometre wide east–west trending synclinal trough structure in which basement–cover contacts differ in the north and the south, suggesting tectonic interleaving during a prograde, D<jats:sub>1</jats:sub> thickening event. Subsequent conditions reached low-medium pressure granulite grade, and structures can be divided into two groups, D<jats:sub>2</jats:sub> and D<jats:sub>3</jats:sub>, each defined by a unique lineation direction and shear sense. D<jats:sub>2</jats:sub> structures which are associated with the dominant gneissic foliation in much of the Larsemann Hills, contain a moderately east-plunging lineation indicative of west-directed thrusting. D<jats:sub>2</jats:sub> comprises a colinear fold sequence that evolved from early intrafolial folds to late upright folds. D<jats:sub>3</jats:sub> structures are associated with a high-strain zone, to the south of the Larsemann Hills, where S<jats:sub>3</jats:sub> is the dominant gneissic layering and folds sequences resemble D<jats:sub>2</jats:sub> folding. Outside the D<jats:sub>3</jats:sub> high-strain zone occurs a low-strain D<jats:sub>3</jats:sub> window, preserving low-strain D<jats:sub>3</jats:sub> structures (minor shear bands and upright folds) that partly re-orient D<jats:sub>2</jats:sub> structures. All structures are truncated by a series of planar pegmatites and parallel D<jats:sub>4</jats:sub> mylonite zones, recording extensional dextral displacements.</jats:p><jats:p>D<jats:sub>2</jats:sub> assemblages include coexisting garnet–orthopyroxene pairs recording peak conditions of ∼ 7 kbar and ∼ 780°C. Subsequent retrograde ... |
format |
Article in Journal/Newspaper |
author |
Carson, C. Dirks, P. Hand, M. Sims, J. Wilson, C. |
spellingShingle |
Carson, C. Dirks, P. Hand, M. Sims, J. Wilson, C. Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica |
author_facet |
Carson, C. Dirks, P. Hand, M. Sims, J. Wilson, C. |
author_sort |
Carson, C. |
title |
Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica |
title_short |
Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica |
title_full |
Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica |
title_fullStr |
Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica |
title_full_unstemmed |
Compressional and extensional tectonics in low-medium pressure granulites from the Larsemann Hills, east Antarctica |
title_sort |
compressional and extensional tectonics in low-medium pressure granulites from the larsemann hills, east antarctica |
publisher |
Cambridge University Press |
publishDate |
1995 |
url |
http://hdl.handle.net/2440/13710 https://doi.org/10.1017/S0016756800011729 |
long_lat |
ENVELOPE(76.217,76.217,-69.400,-69.400) |
geographic |
East Antarctica Larsemann Hills |
geographic_facet |
East Antarctica Larsemann Hills |
genre |
Antarc* Antarctica East Antarctica |
genre_facet |
Antarc* Antarctica East Antarctica |
op_relation |
Geological Magazine, 1995; 132(2):151-170 0016-7568 1469-5081 http://hdl.handle.net/2440/13710 doi:10.1017/S0016756800011729 Hand, M. [0000-0003-3743-9706] |
op_rights |
Copyright © Cambridge University Press 1995 |
op_doi |
https://doi.org/10.1017/S0016756800011729 |
container_title |
Geological Magazine |
container_volume |
132 |
container_issue |
2 |
container_start_page |
151 |
op_container_end_page |
170 |
_version_ |
1766187450496974848 |