Is the Bounty Trough, off New Zealand, an aborted rift?
Remarkably little is known about the Cretaceous rifting process between New Zealand and Antarctica as well as within the submarine parts of the microcontinent of New Zealand itself. The Bounty Trough offers good insights into these break-up processes. Here we present results from a combined gravity,...
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ftawi:oai:epic.awi.de:13952 2023-09-05T13:13:41+02:00 Is the Bounty Trough, off New Zealand, an aborted rift? Grobys, Jan Gohl, Karsten Davy, B. Uenzelmann-Neben, Gabriele Deen, T. Barker, D. H. N. 2007 application/pdf https://epic.awi.de/id/eprint/13952/ https://epic.awi.de/id/eprint/13952/1/Gro2006c.pdf https://doi.org/10.1029/2005JB004229 https://hdl.handle.net/10013/epic.24305 https://hdl.handle.net/10013/epic.24305.d001 unknown https://epic.awi.de/id/eprint/13952/1/Gro2006c.pdf https://hdl.handle.net/10013/epic.24305.d001 Grobys, J. , Gohl, K. orcid:0000-0002-9558-2116 , Davy, B. , Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Deen, T. and Barker, D. H. N. (2007) Is the Bounty Trough, off New Zealand, an aborted rift? , Journal of geophysical research-solid earth, 112, B03103 . doi:10.1029/2005JB004229, <https://doi.org/10.1029/2005JB004229,> , hdl:10013/epic.24305 EPIC3Journal of geophysical research-solid earth, 112, B03103 Article isiRev 2007 ftawi https://doi.org/10.1029/2005JB004229 2023-08-22T19:50:53Z Remarkably little is known about the Cretaceous rifting process between New Zealand and Antarctica as well as within the submarine parts of the microcontinent of New Zealand itself. The Bounty Trough offers good insights into these break-up processes. Here we present results from a combined gravity, multichannel seismic and wide-angle reflection/refraction seismic transect across the Bounty Trough and interpret this on the basis of velocity distribution and crustal composition derived from Poisson's ratio and P-wave velocity. The lower crust exhibits a high-velocity (vp "ca." 7 - 7.7 km/s, vs "ca." 3.9 - 4.5 km/s), high-density body ("rho" "equals" 3.02 kg/cm³) at the location of the most thinned crust of the Bounty Trough. In this part, crustal thickness is reduced from 22 - 24 km beneath Chatham Rise and Campbell Plateau to about 9 km. We interpret this high-velocity/density body as a magmatic intrusion into a thinned continental crust. Our results show that the Cretaceous rifting of the Bounty Trough is very likely not the result of back-arc extension caused by the Hikurangi Plateau subduction in the Gondwana margin, but of continental break-up processes related to the separation of New Zealand from Antarctica. Rifting ceased at the onset of seafloor spreading, so that only little oceanic crust was produced in the Middle Bounty Trough. Comparisons with the Oslo Rift and the Ethiopian/Kenya Rift indicate analogue systems and imply a stretching model that combines uniform stretching and simple shear extension. Article in Journal/Newspaper Antarc* Antarctica Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Bounty Trough ENVELOPE(178.070,178.070,-45.499,-45.499) Campbell Plateau ENVELOPE(171.000,171.000,-50.667,-50.667) New Zealand Rho ENVELOPE(-63.000,-63.000,-64.300,-64.300) Journal of Geophysical Research 112 B3 |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Remarkably little is known about the Cretaceous rifting process between New Zealand and Antarctica as well as within the submarine parts of the microcontinent of New Zealand itself. The Bounty Trough offers good insights into these break-up processes. Here we present results from a combined gravity, multichannel seismic and wide-angle reflection/refraction seismic transect across the Bounty Trough and interpret this on the basis of velocity distribution and crustal composition derived from Poisson's ratio and P-wave velocity. The lower crust exhibits a high-velocity (vp "ca." 7 - 7.7 km/s, vs "ca." 3.9 - 4.5 km/s), high-density body ("rho" "equals" 3.02 kg/cm³) at the location of the most thinned crust of the Bounty Trough. In this part, crustal thickness is reduced from 22 - 24 km beneath Chatham Rise and Campbell Plateau to about 9 km. We interpret this high-velocity/density body as a magmatic intrusion into a thinned continental crust. Our results show that the Cretaceous rifting of the Bounty Trough is very likely not the result of back-arc extension caused by the Hikurangi Plateau subduction in the Gondwana margin, but of continental break-up processes related to the separation of New Zealand from Antarctica. Rifting ceased at the onset of seafloor spreading, so that only little oceanic crust was produced in the Middle Bounty Trough. Comparisons with the Oslo Rift and the Ethiopian/Kenya Rift indicate analogue systems and imply a stretching model that combines uniform stretching and simple shear extension. |
format |
Article in Journal/Newspaper |
author |
Grobys, Jan Gohl, Karsten Davy, B. Uenzelmann-Neben, Gabriele Deen, T. Barker, D. H. N. |
spellingShingle |
Grobys, Jan Gohl, Karsten Davy, B. Uenzelmann-Neben, Gabriele Deen, T. Barker, D. H. N. Is the Bounty Trough, off New Zealand, an aborted rift? |
author_facet |
Grobys, Jan Gohl, Karsten Davy, B. Uenzelmann-Neben, Gabriele Deen, T. Barker, D. H. N. |
author_sort |
Grobys, Jan |
title |
Is the Bounty Trough, off New Zealand, an aborted rift? |
title_short |
Is the Bounty Trough, off New Zealand, an aborted rift? |
title_full |
Is the Bounty Trough, off New Zealand, an aborted rift? |
title_fullStr |
Is the Bounty Trough, off New Zealand, an aborted rift? |
title_full_unstemmed |
Is the Bounty Trough, off New Zealand, an aborted rift? |
title_sort |
is the bounty trough, off new zealand, an aborted rift? |
publishDate |
2007 |
url |
https://epic.awi.de/id/eprint/13952/ https://epic.awi.de/id/eprint/13952/1/Gro2006c.pdf https://doi.org/10.1029/2005JB004229 https://hdl.handle.net/10013/epic.24305 https://hdl.handle.net/10013/epic.24305.d001 |
long_lat |
ENVELOPE(178.070,178.070,-45.499,-45.499) ENVELOPE(171.000,171.000,-50.667,-50.667) ENVELOPE(-63.000,-63.000,-64.300,-64.300) |
geographic |
Bounty Trough Campbell Plateau New Zealand Rho |
geographic_facet |
Bounty Trough Campbell Plateau New Zealand Rho |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
EPIC3Journal of geophysical research-solid earth, 112, B03103 |
op_relation |
https://epic.awi.de/id/eprint/13952/1/Gro2006c.pdf https://hdl.handle.net/10013/epic.24305.d001 Grobys, J. , Gohl, K. orcid:0000-0002-9558-2116 , Davy, B. , Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Deen, T. and Barker, D. H. N. (2007) Is the Bounty Trough, off New Zealand, an aborted rift? , Journal of geophysical research-solid earth, 112, B03103 . doi:10.1029/2005JB004229, <https://doi.org/10.1029/2005JB004229,> , hdl:10013/epic.24305 |
op_doi |
https://doi.org/10.1029/2005JB004229 |
container_title |
Journal of Geophysical Research |
container_volume |
112 |
container_issue |
B3 |
_version_ |
1776204878016675840 |