Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes
We present the results of a study designed to investigate and compare the seismic characteristics of the once contiguous terranes of eastern Gondwanaland, now incorporated in five separated continental masses, which, during the Neoproterozoic (∼600 Ma) Pan-African orogeny, suffered a high degree of...
Published in: | Geophysical Journal International |
---|---|
Main Authors: | , , , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2009
|
Subjects: | |
Online Access: | http://gji.oxfordjournals.org/cgi/content/short/176/2/518 https://doi.org/10.1111/j.1365-246X.2008.03965.x |
id |
fthighwire:oai:open-archive.highwire.org:gji:176/2/518 |
---|---|
record_format |
openpolar |
spelling |
fthighwire:oai:open-archive.highwire.org:gji:176/2/518 2023-05-15T14:03:48+02:00 Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes Rai, Abhishek Gaur, V. K. Rai, S. S. Priestley, K. 2009-02-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/176/2/518 https://doi.org/10.1111/j.1365-246X.2008.03965.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/176/2/518 http://dx.doi.org/10.1111/j.1365-246X.2008.03965.x Copyright (C) 2009, Oxford University Press Seismology TEXT 2009 fthighwire https://doi.org/10.1111/j.1365-246X.2008.03965.x 2013-05-28T10:27:18Z We present the results of a study designed to investigate and compare the seismic characteristics of the once contiguous terranes of eastern Gondwanaland, now incorporated in five separated continental masses, which, during the Neoproterozoic (∼600 Ma) Pan-African orogeny, suffered a high degree of thermal stress and deformation. Receiver functions and surface wave data from stations located in East Antarctica, Sri Lanka, the southern-Indian high-grade terranes, Madagascar and the Tanzania–Mozambique belt, were used to determine the shear-wave velocity structure, Moho depth and V P / V S values of the respective crustal segments. This study provides an additional dimension to the otherwise well-documented characteristic petrology of their surface exposures and other geological signatures such as their extensive granulitization and gem formation during the Pan-African event. Analysis of the receiver functions and surface wave data for these seismic stations located on their present day widely distributed continental fragments have been made. It is observed that with the exception of KOD (at Kodaikanal hill), situated on the southern Indian granulites having the thickest crust (∼43.5 km), most of the Pan-African granulitic terranes have a crustal thicknesses of ∼37 ± 0.8 km, with a transition to higher velocity at mid-crustal depths, and that their bulk composition is felsic. Average crustal V P / V S values (1.704 ± 0.03) and thicknesses (37.8 ± 0.8 km), for four stations (SYO, PALK, TRV and ABPO), now located in East Antarctica, Sri Lanka, India and Madagascar, respectively, show remarkable similarity, indicating that the Pan-African orogeny was extensive enough to reorder the crustal structure of a wide region with a broadly similar stamp. Text Antarc* Antarctica East Antarctica HighWire Press (Stanford University) East Antarctica Indian Geophysical Journal International 176 2 518 528 |
institution |
Open Polar |
collection |
HighWire Press (Stanford University) |
op_collection_id |
fthighwire |
language |
English |
topic |
Seismology |
spellingShingle |
Seismology Rai, Abhishek Gaur, V. K. Rai, S. S. Priestley, K. Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes |
topic_facet |
Seismology |
description |
We present the results of a study designed to investigate and compare the seismic characteristics of the once contiguous terranes of eastern Gondwanaland, now incorporated in five separated continental masses, which, during the Neoproterozoic (∼600 Ma) Pan-African orogeny, suffered a high degree of thermal stress and deformation. Receiver functions and surface wave data from stations located in East Antarctica, Sri Lanka, the southern-Indian high-grade terranes, Madagascar and the Tanzania–Mozambique belt, were used to determine the shear-wave velocity structure, Moho depth and V P / V S values of the respective crustal segments. This study provides an additional dimension to the otherwise well-documented characteristic petrology of their surface exposures and other geological signatures such as their extensive granulitization and gem formation during the Pan-African event. Analysis of the receiver functions and surface wave data for these seismic stations located on their present day widely distributed continental fragments have been made. It is observed that with the exception of KOD (at Kodaikanal hill), situated on the southern Indian granulites having the thickest crust (∼43.5 km), most of the Pan-African granulitic terranes have a crustal thicknesses of ∼37 ± 0.8 km, with a transition to higher velocity at mid-crustal depths, and that their bulk composition is felsic. Average crustal V P / V S values (1.704 ± 0.03) and thicknesses (37.8 ± 0.8 km), for four stations (SYO, PALK, TRV and ABPO), now located in East Antarctica, Sri Lanka, India and Madagascar, respectively, show remarkable similarity, indicating that the Pan-African orogeny was extensive enough to reorder the crustal structure of a wide region with a broadly similar stamp. |
format |
Text |
author |
Rai, Abhishek Gaur, V. K. Rai, S. S. Priestley, K. |
author_facet |
Rai, Abhishek Gaur, V. K. Rai, S. S. Priestley, K. |
author_sort |
Rai, Abhishek |
title |
Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes |
title_short |
Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes |
title_full |
Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes |
title_fullStr |
Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes |
title_full_unstemmed |
Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes |
title_sort |
seismic signatures of the pan-african orogeny: implications for southern indian high-grade terranes |
publisher |
Oxford University Press |
publishDate |
2009 |
url |
http://gji.oxfordjournals.org/cgi/content/short/176/2/518 https://doi.org/10.1111/j.1365-246X.2008.03965.x |
geographic |
East Antarctica Indian |
geographic_facet |
East Antarctica Indian |
genre |
Antarc* Antarctica East Antarctica |
genre_facet |
Antarc* Antarctica East Antarctica |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/176/2/518 http://dx.doi.org/10.1111/j.1365-246X.2008.03965.x |
op_rights |
Copyright (C) 2009, Oxford University Press |
op_doi |
https://doi.org/10.1111/j.1365-246X.2008.03965.x |
container_title |
Geophysical Journal International |
container_volume |
176 |
container_issue |
2 |
container_start_page |
518 |
op_container_end_page |
528 |
_version_ |
1766274660013441024 |