Ambient noise tomography of the East African Rift in Mozambique
Seismic ambient noise tomography is applied to central and southern Mozambique, located in the tip of the East African Rift (EAR). The deployment of MOZART seismic network, with a total of 30 broad-band stations continuously recording for 26 months, allowed us to carry out the first tomographic stud...
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Online Access: | https://discovery.ucl.ac.uk/id/eprint/1496138/8/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/7/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique%20-%20Supplementary%20file.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/ |
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ftucl:oai:eprints.ucl.ac.uk.OAI2:1496138 2023-12-24T10:10:49+01:00 Ambient noise tomography of the East African Rift in Mozambique Domingues, A Silveira, G Ferreira, AMG Chang, S-J Custódio, S Fonseca, JFBD 2016-03 text https://discovery.ucl.ac.uk/id/eprint/1496138/8/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/7/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique%20-%20Supplementary%20file.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/ eng eng https://discovery.ucl.ac.uk/id/eprint/1496138/8/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/7/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique%20-%20Supplementary%20file.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/ open Geophysical Journal International , 204 (3) pp. 1565-1578. (2016) Seismic tomography Continental margins: divergent Crustal structure Article 2016 ftucl 2023-11-27T13:07:32Z Seismic ambient noise tomography is applied to central and southern Mozambique, located in the tip of the East African Rift (EAR). The deployment of MOZART seismic network, with a total of 30 broad-band stations continuously recording for 26 months, allowed us to carry out the first tomographic study of the crust under this region, which until now remained largely unexplored at this scale. From cross-correlations extracted from coherent noise we obtained Rayleigh wave group velocity dispersion curves for the period range 5–40 s. These dispersion relations were inverted to produce group velocity maps, and 1-D shear wave velocity profiles at selected points. High group velocities are observed at all periods on the eastern edge of the Kaapvaal and Zimbabwe cratons, in agreement with the findings of previous studies. Further east, a pronounced slow anomaly is observed in central and southern Mozambique, where the rifting between southern Africa and Antarctica created a passive margin in the Mesozoic, and further rifting is currently happening as a result of the southward propagation of the EAR. In this study, we also addressed the question concerning the nature of the crust (continental versus oceanic) in the Mozambique Coastal Plains (MCP), still in debate. Our data do not support previous suggestions that the MCP are floored by oceanic crust since a shallow Moho could not be detected, and we discuss an alternative explanation for its ocean-like magnetic signature. Our velocity maps suggest that the crystalline basement of the Zimbabwe craton may extend further east well into Mozambique underneath the sediment cover, contrary to what is usually assumed, while further south the Kaapval craton passes into slow rifted crust at the Lebombo monocline as expected. The sharp passage from fast crust to slow crust on the northern part of the study area coincides with the seismically active NNE-SSW Urema rift, while further south the Mazenga graben adopts an N-S direction parallel to the eastern limit of the Kaapvaal craton. ... Article in Journal/Newspaper Antarc* Antarctica University College London: UCL Discovery |
institution |
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University College London: UCL Discovery |
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ftucl |
language |
English |
topic |
Seismic tomography Continental margins: divergent Crustal structure |
spellingShingle |
Seismic tomography Continental margins: divergent Crustal structure Domingues, A Silveira, G Ferreira, AMG Chang, S-J Custódio, S Fonseca, JFBD Ambient noise tomography of the East African Rift in Mozambique |
topic_facet |
Seismic tomography Continental margins: divergent Crustal structure |
description |
Seismic ambient noise tomography is applied to central and southern Mozambique, located in the tip of the East African Rift (EAR). The deployment of MOZART seismic network, with a total of 30 broad-band stations continuously recording for 26 months, allowed us to carry out the first tomographic study of the crust under this region, which until now remained largely unexplored at this scale. From cross-correlations extracted from coherent noise we obtained Rayleigh wave group velocity dispersion curves for the period range 5–40 s. These dispersion relations were inverted to produce group velocity maps, and 1-D shear wave velocity profiles at selected points. High group velocities are observed at all periods on the eastern edge of the Kaapvaal and Zimbabwe cratons, in agreement with the findings of previous studies. Further east, a pronounced slow anomaly is observed in central and southern Mozambique, where the rifting between southern Africa and Antarctica created a passive margin in the Mesozoic, and further rifting is currently happening as a result of the southward propagation of the EAR. In this study, we also addressed the question concerning the nature of the crust (continental versus oceanic) in the Mozambique Coastal Plains (MCP), still in debate. Our data do not support previous suggestions that the MCP are floored by oceanic crust since a shallow Moho could not be detected, and we discuss an alternative explanation for its ocean-like magnetic signature. Our velocity maps suggest that the crystalline basement of the Zimbabwe craton may extend further east well into Mozambique underneath the sediment cover, contrary to what is usually assumed, while further south the Kaapval craton passes into slow rifted crust at the Lebombo monocline as expected. The sharp passage from fast crust to slow crust on the northern part of the study area coincides with the seismically active NNE-SSW Urema rift, while further south the Mazenga graben adopts an N-S direction parallel to the eastern limit of the Kaapvaal craton. ... |
format |
Article in Journal/Newspaper |
author |
Domingues, A Silveira, G Ferreira, AMG Chang, S-J Custódio, S Fonseca, JFBD |
author_facet |
Domingues, A Silveira, G Ferreira, AMG Chang, S-J Custódio, S Fonseca, JFBD |
author_sort |
Domingues, A |
title |
Ambient noise tomography of the East African Rift in Mozambique |
title_short |
Ambient noise tomography of the East African Rift in Mozambique |
title_full |
Ambient noise tomography of the East African Rift in Mozambique |
title_fullStr |
Ambient noise tomography of the East African Rift in Mozambique |
title_full_unstemmed |
Ambient noise tomography of the East African Rift in Mozambique |
title_sort |
ambient noise tomography of the east african rift in mozambique |
publishDate |
2016 |
url |
https://discovery.ucl.ac.uk/id/eprint/1496138/8/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/7/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique%20-%20Supplementary%20file.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/ |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
Geophysical Journal International , 204 (3) pp. 1565-1578. (2016) |
op_relation |
https://discovery.ucl.ac.uk/id/eprint/1496138/8/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/7/Domingues_et_al%20Ambient%20noise%20tomography%20of%20the%20East%20African%20Rift%20in%20Mozambique%20-%20Supplementary%20file.pdf https://discovery.ucl.ac.uk/id/eprint/1496138/ |
op_rights |
open |
_version_ |
1786157593340674048 |