A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica
A paleomagnetic study of the late Middle to possibly early Late Cambrian Liberty Hills Formation in the Ellsworth Mountains, Antarctica, reveals a stable magnetization with positive fold and reversal tests. The paleopole is based on 16 sites from volcanic and sedimentary rocks and lies at lat 7.3°N...
Published in: | The Journal of Geology |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
University of Chicago Press
2000
|
Subjects: | |
Online Access: | http://nora.nerc.ac.uk/id/eprint/502121/ https://doi.org/10.1086/314408 |
id |
ftnerc:oai:nora.nerc.ac.uk:502121 |
---|---|
record_format |
openpolar |
spelling |
ftnerc:oai:nora.nerc.ac.uk:502121 2024-02-04T09:55:49+01:00 A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica Randall, Darren E. Curtis, Michael L. Millar, Ian L. 2000 http://nora.nerc.ac.uk/id/eprint/502121/ https://doi.org/10.1086/314408 unknown University of Chicago Press Randall, Darren E.; Curtis, Michael L.; Millar, Ian L. 2000 A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica. The Journal of Geology, 108 (4). 403-425. https://doi.org/10.1086/314408 <https://doi.org/10.1086/314408> Earth Sciences Publication - Article PeerReviewed 2000 ftnerc https://doi.org/10.1086/314408 2024-01-05T00:03:05Z A paleomagnetic study of the late Middle to possibly early Late Cambrian Liberty Hills Formation in the Ellsworth Mountains, Antarctica, reveals a stable magnetization with positive fold and reversal tests. The paleopole is based on 16 sites from volcanic and sedimentary rocks and lies at lat 7.3°N and long 326.3°E ( $\mathrm{A}\,_{95}=6.0^{\circ }$ ). The new paleomagnetic data support the view that the Ellsworth Mountains are part of a microplate—the Ellsworth‐Whitmore Mountains crustal block—that rotated independently of the main Gondwana continental blocks during breakup. The Liberty Hills pole differs from both previous poles recovered from Cambrian rocks in the Ellsworth Mountains and from the available Gondwana reference pole data. Our pole indicates a more northerly prebreakup position for the Ellsworth Mountains than previously suggested, contradicting the overwhelming geologic evidence for a prebreakup position close to southern Africa. The reasons for this are uncertain, but we suggest that problems with the Gondwana apparent polar wander path may be important. More well constrained, early Paleozoic paleomagnetic data are required from the Ellsworth Mountains and the Gondwana continents if the data are to constrain further the Middle‐Late Cambrian location of the Ellsworth‐Whitmore Mountains block. Article in Journal/Newspaper Antarc* Antarctica Natural Environment Research Council: NERC Open Research Archive Ellsworth Mountains ENVELOPE(-85.000,-85.000,-78.750,-78.750) Whitmore Mountains ENVELOPE(-104.000,-104.000,-82.500,-82.500) Liberty Hills ENVELOPE(-82.917,-82.917,-80.100,-80.100) The Journal of Geology 108 4 403 425 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Randall, Darren E. Curtis, Michael L. Millar, Ian L. A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica |
topic_facet |
Earth Sciences |
description |
A paleomagnetic study of the late Middle to possibly early Late Cambrian Liberty Hills Formation in the Ellsworth Mountains, Antarctica, reveals a stable magnetization with positive fold and reversal tests. The paleopole is based on 16 sites from volcanic and sedimentary rocks and lies at lat 7.3°N and long 326.3°E ( $\mathrm{A}\,_{95}=6.0^{\circ }$ ). The new paleomagnetic data support the view that the Ellsworth Mountains are part of a microplate—the Ellsworth‐Whitmore Mountains crustal block—that rotated independently of the main Gondwana continental blocks during breakup. The Liberty Hills pole differs from both previous poles recovered from Cambrian rocks in the Ellsworth Mountains and from the available Gondwana reference pole data. Our pole indicates a more northerly prebreakup position for the Ellsworth Mountains than previously suggested, contradicting the overwhelming geologic evidence for a prebreakup position close to southern Africa. The reasons for this are uncertain, but we suggest that problems with the Gondwana apparent polar wander path may be important. More well constrained, early Paleozoic paleomagnetic data are required from the Ellsworth Mountains and the Gondwana continents if the data are to constrain further the Middle‐Late Cambrian location of the Ellsworth‐Whitmore Mountains block. |
format |
Article in Journal/Newspaper |
author |
Randall, Darren E. Curtis, Michael L. Millar, Ian L. |
author_facet |
Randall, Darren E. Curtis, Michael L. Millar, Ian L. |
author_sort |
Randall, Darren E. |
title |
A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica |
title_short |
A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica |
title_full |
A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica |
title_fullStr |
A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica |
title_full_unstemmed |
A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica |
title_sort |
new late middle cambrian paleomagnetic pole for the ellsworth mountains, antarctica |
publisher |
University of Chicago Press |
publishDate |
2000 |
url |
http://nora.nerc.ac.uk/id/eprint/502121/ https://doi.org/10.1086/314408 |
long_lat |
ENVELOPE(-85.000,-85.000,-78.750,-78.750) ENVELOPE(-104.000,-104.000,-82.500,-82.500) ENVELOPE(-82.917,-82.917,-80.100,-80.100) |
geographic |
Ellsworth Mountains Whitmore Mountains Liberty Hills |
geographic_facet |
Ellsworth Mountains Whitmore Mountains Liberty Hills |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_relation |
Randall, Darren E.; Curtis, Michael L.; Millar, Ian L. 2000 A new Late Middle Cambrian paleomagnetic pole for the Ellsworth Mountains, Antarctica. The Journal of Geology, 108 (4). 403-425. https://doi.org/10.1086/314408 <https://doi.org/10.1086/314408> |
op_doi |
https://doi.org/10.1086/314408 |
container_title |
The Journal of Geology |
container_volume |
108 |
container_issue |
4 |
container_start_page |
403 |
op_container_end_page |
425 |
_version_ |
1789959986487492608 |