Airborne gravity reveals interior of Antarctic volcano
Understanding Antarctic volcanoes is important as they provide a window on magmatic and tectonic processes of the Antarctic plate and contain datable records of ice-sheet changes. We present the results from the first detailed airborne radar and gravity surveys across James Ross Island, northern Ant...
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ftnerc:oai:nora.nerc.ac.uk:11086 2024-02-11T09:57:43+01:00 Airborne gravity reveals interior of Antarctic volcano Jordan, Tom A. Ferraccioli, Fausto Jones, P.C Smellie, J.L. Ghidella, M. Corr, Hugh 2009 http://nora.nerc.ac.uk/id/eprint/11086/ https://doi.org/10.1016/j.pepi.2009.03.004 unknown Elsevier Jordan, Tom A. orcid:0000-0003-2780-1986 Ferraccioli, Fausto orcid:0000-0002-9347-4736 Jones, P.C; Smellie, J.L.; Ghidella, M.; Corr, Hugh. 2009 Airborne gravity reveals interior of Antarctic volcano. Physics of the Earth and Planetary Interiors, 175 (3-4). 127-136. https://doi.org/10.1016/j.pepi.2009.03.004 <https://doi.org/10.1016/j.pepi.2009.03.004> Glaciology Physics Earth Sciences Publication - Article PeerReviewed 2009 ftnerc https://doi.org/10.1016/j.pepi.2009.03.004 2024-01-26T00:03:20Z Understanding Antarctic volcanoes is important as they provide a window on magmatic and tectonic processes of the Antarctic plate and contain datable records of ice-sheet changes. We present the results from the first detailed airborne radar and gravity surveys across James Ross Island, northern Antarctic Peninsula, which is dominated by Mt Haddington, an ice-covered Miocene-Recent alkaline stratovolcano. The surveys provide new insights into the subsurface structure of the volcano and hence its development, which are unavailable from the surface geology alone. We show that Mt Haddington is associated with a significant negative Bouguer gravity anomaly (>= 26 mGal), which suggests that there has not been significant pooling and solidification of a dense shallow-level mafic magma chamber during the growth of the volcano over at least the past 6 m.y., which is consistent with independent geochemical evidence. Simple flexural isostatic models cannot explain the localised negative Bouguer anomaly. 3D modelling techniques show that the negative anomaly is best explained by a shallow, low-density intra-crustal body with its top close to, or at, the surface. Although comparable gravity anomalies are commonly associated with large (similar to 20 km) ash-filled calderas, as seen at Yellowstone or Toba, there is no geological evidence on James Ross Island for a similar structure. We therefore propose that the James Ross Island volcanic edifice subsided into the thick underlying pile of relatively soft Jurassic and Cretaceous sediments, which were displaced by low-density hyaloclastite breccia. The type of deformation envisaged is similar to that associated with Concepciou, or lwaki volcanoes in South America, although Mt Haddington is much larger. (C) 2009 Elsevier B.V. All rights reserved. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Ice Sheet James Ross Island Ross Island Natural Environment Research Council: NERC Open Research Archive Antarctic The Antarctic Antarctic Peninsula Ross Island Haddington ENVELOPE(-57.733,-57.733,-64.250,-64.250) Physics of the Earth and Planetary Interiors 175 3-4 127 136 |
institution |
Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Glaciology Physics Earth Sciences |
spellingShingle |
Glaciology Physics Earth Sciences Jordan, Tom A. Ferraccioli, Fausto Jones, P.C Smellie, J.L. Ghidella, M. Corr, Hugh Airborne gravity reveals interior of Antarctic volcano |
topic_facet |
Glaciology Physics Earth Sciences |
description |
Understanding Antarctic volcanoes is important as they provide a window on magmatic and tectonic processes of the Antarctic plate and contain datable records of ice-sheet changes. We present the results from the first detailed airborne radar and gravity surveys across James Ross Island, northern Antarctic Peninsula, which is dominated by Mt Haddington, an ice-covered Miocene-Recent alkaline stratovolcano. The surveys provide new insights into the subsurface structure of the volcano and hence its development, which are unavailable from the surface geology alone. We show that Mt Haddington is associated with a significant negative Bouguer gravity anomaly (>= 26 mGal), which suggests that there has not been significant pooling and solidification of a dense shallow-level mafic magma chamber during the growth of the volcano over at least the past 6 m.y., which is consistent with independent geochemical evidence. Simple flexural isostatic models cannot explain the localised negative Bouguer anomaly. 3D modelling techniques show that the negative anomaly is best explained by a shallow, low-density intra-crustal body with its top close to, or at, the surface. Although comparable gravity anomalies are commonly associated with large (similar to 20 km) ash-filled calderas, as seen at Yellowstone or Toba, there is no geological evidence on James Ross Island for a similar structure. We therefore propose that the James Ross Island volcanic edifice subsided into the thick underlying pile of relatively soft Jurassic and Cretaceous sediments, which were displaced by low-density hyaloclastite breccia. The type of deformation envisaged is similar to that associated with Concepciou, or lwaki volcanoes in South America, although Mt Haddington is much larger. (C) 2009 Elsevier B.V. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Jordan, Tom A. Ferraccioli, Fausto Jones, P.C Smellie, J.L. Ghidella, M. Corr, Hugh |
author_facet |
Jordan, Tom A. Ferraccioli, Fausto Jones, P.C Smellie, J.L. Ghidella, M. Corr, Hugh |
author_sort |
Jordan, Tom A. |
title |
Airborne gravity reveals interior of Antarctic volcano |
title_short |
Airborne gravity reveals interior of Antarctic volcano |
title_full |
Airborne gravity reveals interior of Antarctic volcano |
title_fullStr |
Airborne gravity reveals interior of Antarctic volcano |
title_full_unstemmed |
Airborne gravity reveals interior of Antarctic volcano |
title_sort |
airborne gravity reveals interior of antarctic volcano |
publisher |
Elsevier |
publishDate |
2009 |
url |
http://nora.nerc.ac.uk/id/eprint/11086/ https://doi.org/10.1016/j.pepi.2009.03.004 |
long_lat |
ENVELOPE(-57.733,-57.733,-64.250,-64.250) |
geographic |
Antarctic The Antarctic Antarctic Peninsula Ross Island Haddington |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula Ross Island Haddington |
genre |
Antarc* Antarctic Antarctic Peninsula Ice Sheet James Ross Island Ross Island |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Ice Sheet James Ross Island Ross Island |
op_relation |
Jordan, Tom A. orcid:0000-0003-2780-1986 Ferraccioli, Fausto orcid:0000-0002-9347-4736 Jones, P.C; Smellie, J.L.; Ghidella, M.; Corr, Hugh. 2009 Airborne gravity reveals interior of Antarctic volcano. Physics of the Earth and Planetary Interiors, 175 (3-4). 127-136. https://doi.org/10.1016/j.pepi.2009.03.004 <https://doi.org/10.1016/j.pepi.2009.03.004> |
op_doi |
https://doi.org/10.1016/j.pepi.2009.03.004 |
container_title |
Physics of the Earth and Planetary Interiors |
container_volume |
175 |
container_issue |
3-4 |
container_start_page |
127 |
op_container_end_page |
136 |
_version_ |
1790593268387414016 |