Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data
The Dufek intrusion, in the northern part of the Pensacola Mountains, Antarctica, is part of an extensive, Middle Jurassic igneous province that was related to, and emplaced just prior to Gondwana break-up. It has been described as one of the largest layered gabbro intrusions in the world, and is ex...
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ftnerc:oai:nora.nerc.ac.uk:504012 2024-02-11T09:58:23+01:00 Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data Ferris, Julie Johnson, Ash Storey, Bryan 1998 http://nora.nerc.ac.uk/id/eprint/504012/ https://doi.org/10.1016/S0012-821X(97)00165-9 unknown Elsevier Ferris, Julie; Johnson, Ash; Storey, Bryan. 1998 Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data. Earth and Planetary Science Letters, 154 (1-4). 185-202. https://doi.org/10.1016/S0012-821X(97)00165-9 <https://doi.org/10.1016/S0012-821X(97)00165-9> Publication - Article PeerReviewed 1998 ftnerc https://doi.org/10.1016/S0012-821X(97)00165-9 2024-01-26T00:03:24Z The Dufek intrusion, in the northern part of the Pensacola Mountains, Antarctica, is part of an extensive, Middle Jurassic igneous province that was related to, and emplaced just prior to Gondwana break-up. It has been described as one of the largest layered gabbro intrusions in the world, and is exposed as two non-overlapping gabbro sequences in the Dufek Massif and the Forrestal Range. A new compilation of aeromagnetic data over the Dufek intrusion and surrounding region is based on mapping at two scales, a 2 km grid spacing over the Dufek intrusion, and a 6 km grid spacing over the surrounding region. Advanced processing of the data is used to produce an analytical signal and a terrace map as a basis for a new interpretation. Modelling and interpretation of the data show that the Dufek intrusion is not as extensive as was thought, and that it is more similar in size to the Stillwater Intrusion in North America, than to the Bushveld Complex in South Africa to which it has previously been compared. The reduced size of the Dufek intrusion is due to reinterpretation of an anomaly over Berkner Island, to the north of the Pensacola Mountains, as that of an uplifted basement block rather than a continuation of the Dufek intrusion. The Dufek intrusion is modelled as two separate intrusive phases of a composite intrusion. The main part is a dipping intrusive sheet displaced by a normal fault which accounts for two parallel magnetic anomalies over the Forrestal Range. The minor part forms the Dufek Massif itself, which the magnetic data show was emplaced on a separate trend and is of a shallower origin than the Forrestal phase. Magnetic lineaments on the compilation map are used to establish a possible chronology of events. We suggest that the emplacement of both phases of the Dufek intrusion was preceded by a period of extensional block faulting which uplifted the Berkner Island basement block, and was succeeded by a further period of extensional faulting involving a component of strike–slip deformation during the ... Article in Journal/Newspaper Antarc* Antarctica Berkner Island Natural Environment Research Council: NERC Open Research Archive Berkner Island ENVELOPE(-48.117,-48.117,-79.333,-79.333) Pensacola Mountains ENVELOPE(-58.000,-58.000,-83.500,-83.500) Dufek Massif ENVELOPE(-52.500,-52.500,-82.500,-82.500) Forrestal Range ENVELOPE(-48.500,-48.500,-82.667,-82.667) Earth and Planetary Science Letters 154 1-4 185 202 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
The Dufek intrusion, in the northern part of the Pensacola Mountains, Antarctica, is part of an extensive, Middle Jurassic igneous province that was related to, and emplaced just prior to Gondwana break-up. It has been described as one of the largest layered gabbro intrusions in the world, and is exposed as two non-overlapping gabbro sequences in the Dufek Massif and the Forrestal Range. A new compilation of aeromagnetic data over the Dufek intrusion and surrounding region is based on mapping at two scales, a 2 km grid spacing over the Dufek intrusion, and a 6 km grid spacing over the surrounding region. Advanced processing of the data is used to produce an analytical signal and a terrace map as a basis for a new interpretation. Modelling and interpretation of the data show that the Dufek intrusion is not as extensive as was thought, and that it is more similar in size to the Stillwater Intrusion in North America, than to the Bushveld Complex in South Africa to which it has previously been compared. The reduced size of the Dufek intrusion is due to reinterpretation of an anomaly over Berkner Island, to the north of the Pensacola Mountains, as that of an uplifted basement block rather than a continuation of the Dufek intrusion. The Dufek intrusion is modelled as two separate intrusive phases of a composite intrusion. The main part is a dipping intrusive sheet displaced by a normal fault which accounts for two parallel magnetic anomalies over the Forrestal Range. The minor part forms the Dufek Massif itself, which the magnetic data show was emplaced on a separate trend and is of a shallower origin than the Forrestal phase. Magnetic lineaments on the compilation map are used to establish a possible chronology of events. We suggest that the emplacement of both phases of the Dufek intrusion was preceded by a period of extensional block faulting which uplifted the Berkner Island basement block, and was succeeded by a further period of extensional faulting involving a component of strike–slip deformation during the ... |
format |
Article in Journal/Newspaper |
author |
Ferris, Julie Johnson, Ash Storey, Bryan |
spellingShingle |
Ferris, Julie Johnson, Ash Storey, Bryan Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data |
author_facet |
Ferris, Julie Johnson, Ash Storey, Bryan |
author_sort |
Ferris, Julie |
title |
Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data |
title_short |
Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data |
title_full |
Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data |
title_fullStr |
Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data |
title_full_unstemmed |
Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data |
title_sort |
form and extent of the dufek intrusion, antarctica, from newly compiled aeromagnetic data |
publisher |
Elsevier |
publishDate |
1998 |
url |
http://nora.nerc.ac.uk/id/eprint/504012/ https://doi.org/10.1016/S0012-821X(97)00165-9 |
long_lat |
ENVELOPE(-48.117,-48.117,-79.333,-79.333) ENVELOPE(-58.000,-58.000,-83.500,-83.500) ENVELOPE(-52.500,-52.500,-82.500,-82.500) ENVELOPE(-48.500,-48.500,-82.667,-82.667) |
geographic |
Berkner Island Pensacola Mountains Dufek Massif Forrestal Range |
geographic_facet |
Berkner Island Pensacola Mountains Dufek Massif Forrestal Range |
genre |
Antarc* Antarctica Berkner Island |
genre_facet |
Antarc* Antarctica Berkner Island |
op_relation |
Ferris, Julie; Johnson, Ash; Storey, Bryan. 1998 Form and extent of the Dufek intrusion, Antarctica, from newly compiled aeromagnetic data. Earth and Planetary Science Letters, 154 (1-4). 185-202. https://doi.org/10.1016/S0012-821X(97)00165-9 <https://doi.org/10.1016/S0012-821X(97)00165-9> |
op_doi |
https://doi.org/10.1016/S0012-821X(97)00165-9 |
container_title |
Earth and Planetary Science Letters |
container_volume |
154 |
container_issue |
1-4 |
container_start_page |
185 |
op_container_end_page |
202 |
_version_ |
1790594017075920896 |