Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica
We conducted initial palaeomagnetic studies on cores from site AND-2A (77°45.488’S, 165°16.605’E, ~383.57 metres water depth). A total of 813 samples were collected that span from the top of the section down to the base at 1138.54 metres below sea floor (mbsf). Samples were collected every one or tw...
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Language: | English |
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Terra Antartica
2009
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Online Access: | http://hdl.handle.net/2122/6033 |
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ftingv:oai:www.earth-prints.org:2122/6033 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
Earth-Prints (Istituto Nazionale di Geofisica e Vulcanologia) |
op_collection_id |
ftingv |
language |
English |
topic |
Magnetostratigraphy ANDRILL Antarctica Paleomagnetism 04. Solid Earth::04.04. Geology::04.04.10. Stratigraphy 04. Solid Earth::04.05. Geomagnetism::04.05.06. Paleomagnetism |
spellingShingle |
Magnetostratigraphy ANDRILL Antarctica Paleomagnetism 04. Solid Earth::04.04. Geology::04.04.10. Stratigraphy 04. Solid Earth::04.05. Geomagnetism::04.05.06. Paleomagnetism Acton, G. Florindo, F. Jovane, L. Lum, B. Ohneiser, C. Sagnotti, L. Strada, E. Verosub, K.L. Wilson, G.S. THE ANDRIL-SMS Science Team Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica |
topic_facet |
Magnetostratigraphy ANDRILL Antarctica Paleomagnetism 04. Solid Earth::04.04. Geology::04.04.10. Stratigraphy 04. Solid Earth::04.05. Geomagnetism::04.05.06. Paleomagnetism |
description |
We conducted initial palaeomagnetic studies on cores from site AND-2A (77°45.488’S, 165°16.605’E, ~383.57 metres water depth). A total of 813 samples were collected that span from the top of the section down to the base at 1138.54 metres below sea floor (mbsf). Samples were collected every one or two metres down the core, with paired (pilot) samples being collected about every ten to twenty metres to allow us to assess the demagnetisation behaviour of the samples using either alternating field (AF) or thermal demagnetisation. With the exception of only a few intervals, AF demagnetisation was observed to resolve a characteristic remanent magnetisation (ChRM) as well or better than thermal demagnetisation. Thermal demagnetisation was particularly ineffective in many intervals owing to thermal alteration that was common above 500°C and was evident in some samples even at low temperatures. Above Lithostratigraphic Unit (LSU) 8 (436.18 mbsf), where lithologies are generally more coarse grained than lower in the section, resolving a ChRM is difficult and recent overprints or a drilling overprint are a concern. Within LSU 8 and below, most samples have a ChRM that can be resolved. The ChRM is most likely an original depositional magnetisation throughout most of this lower section, although orthogonal demagnetisation diagrams contain evidence that normal polarity overprinting affects some intervals. Based on 40Ar/39Ar dates and diatom datums, the magnetozones identified from the base of the hole up to ~266mbsf are consistent with spanning from either Chron C6n (18.748-19.772 Ma) or C6An.1n (20.040-20.213 Ma) up through Chron C5Br (15.160-15.974 Ma). Above this, intervals of constant polarity are isolated within longer stratigraphic intervals of uncertain polarity, making their correlation with the geomagnetic polarity timescale (GPTS) speculative and highly dependent on ages obtained from other dating methods. One exception is a reversed-to-normal polarity transition that occurs at ~31 mbsf and is interpreted to most ... |
author2 |
Acton, G.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Jovane, L.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Lum, B.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Ohneiser, C.; Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Strada, E.; Dipartimento di Scienze della Terra, Università di Siena, Via del Laterino 8, I-53100 Siena – Italy Verosub, K.L.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Wilson, G.S.; Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand THE ANDRIL-SMS Science Team; http://www.andrill.org/projects/sms/team.html Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand Dipartimento di Scienze della Terra, Università di Siena, Via del Laterino 8, I-53100 Siena – Italy http://www.andrill.org/projects/sms/team.html |
format |
Article in Journal/Newspaper |
author |
Acton, G. Florindo, F. Jovane, L. Lum, B. Ohneiser, C. Sagnotti, L. Strada, E. Verosub, K.L. Wilson, G.S. THE ANDRIL-SMS Science Team |
author_facet |
Acton, G. Florindo, F. Jovane, L. Lum, B. Ohneiser, C. Sagnotti, L. Strada, E. Verosub, K.L. Wilson, G.S. THE ANDRIL-SMS Science Team |
author_sort |
Acton, G. |
title |
Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica |
title_short |
Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica |
title_full |
Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica |
title_fullStr |
Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica |
title_full_unstemmed |
Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica |
title_sort |
palaeomagnetism of the and-2a core, andrill southern mcmurdo sound project, antarctica |
publisher |
Terra Antartica |
publishDate |
2009 |
url |
http://hdl.handle.net/2122/6033 |
geographic |
McMurdo Sound |
geographic_facet |
McMurdo Sound |
genre |
Antarc* Antarctica McMurdo Sound |
genre_facet |
Antarc* Antarctica McMurdo Sound |
op_relation |
Terra Antartica /15 (2009) Acton, G., Crampton, J., Di Vincenzo, G., Fielding, C.R., Florindo, F., Hannah, M., Harwood, D., Ishman, S., Johnson, K., Jovane, L., Levy, R., Lum, B., Marcano, C., Mukasa, S., Ohneiser, C., Olney, M., Riesselman, C., Sagnotti, L., Stefano, C., Strada, E., Taviani, M., Tuzzi, E., Verosub, K.L., Wilson, G.S., Zattin, M., and The ANDRILL-SMS Science Team, 2008-2009. Preliminary integrated chronostratigraphy of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica, Terra Antartica, 15, this volume, 211-220. Cande S.C. & Kent D.V., 1995. Revised calibration of the geomagnetic polarity timescale for the Late Cretaceous and Cenozoic. J. Geophys. Res., 100, 6093-6095. Fielding C.R., Atkins C.B., Bassett K.N., Browne G.H., Dunbar G.B., Field B.D., Frank T.D., Krissek L.A., Panter K.S., Passchier S., Pekar S.F., Sandroni S., Talarico F., & the ANDRILL-SMS Science Team, 2008. Sedimentology and Stratigraphy of the AND-2A Core. ANDRILL Southern McMurdo Sound Project, Antarctica. Terra Antartica, 15, this volume, 77-112. Fisher R.A., 1953. Dispersion on a sphere. Proc. R. Soc. London A, 217, 295-305. Gradstein F.M., Ogg J.G., & Smith A.G, 2004. A Geologic Time Scale 2004. Cambridge University Press, Cambridge, United Kingdom, 610 pp. Kirschvink J.L., 1980. The least-squares line and plane and the analysis of palaeomagnetic data. Geophys. J. R. Astron. Soc., 62, 699-718. Kretz R., 1983. Symbols for rock forming minerals. American Mineralogist, 68, 277-279. Panter K.S., Talarico F., Bassett K., Del Carlo P., Field B., Frank T., Hoffman S., Kuhn G., Reichelt L., Sandroni S., Taviani M., Bracciali L., Cornamusini G., von Eynatten, H., Rocchi S., & the ANDRILL-SMS Science Team, 2008-2009. Petrologic and geochemical composition of the AND-2A Core, ANDRILL, Southern McMurdo Sound Project, Antarctica. Terra Antartica, 15, this volume, 147-192. Turner G.M., 2001. Toward an understanding of the mulicomponent magnetization of uplifted Neogene marine sediments in New Zealand, J. Geophys. Res., 106, 6385-6397. Wessel P., & Smith W.H.F., 1998. New, improved version of the Generic Mapping Tools released. Eos Trans. AGU, 79, 579. Wilson G.S., Florindo F., Sagnotti L., Ohneiser C., & the ANDRILLMIS Science Team, 2007. Palaeomagnetism of the AND-1B Core, ANDRILL McMurdo Ice Shelf Project, Antarctica. Terra Antartica, 14, 289-296. Worm H.-U., 1998. On the superparamagnetic-stable single domain transition for magnetite, and frequency dependence of susceptibility. Geophys. J. Int., 133, 201-206. http://hdl.handle.net/2122/6033 |
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1766271545575997440 |
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ftingv:oai:www.earth-prints.org:2122/6033 2023-05-15T14:01:36+02:00 Palaeomagnetism of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica Acton, G. Florindo, F. Jovane, L. Lum, B. Ohneiser, C. Sagnotti, L. Strada, E. Verosub, K.L. Wilson, G.S. THE ANDRIL-SMS Science Team Acton, G.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Jovane, L.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Lum, B.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Ohneiser, C.; Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Strada, E.; Dipartimento di Scienze della Terra, Università di Siena, Via del Laterino 8, I-53100 Siena – Italy Verosub, K.L.; Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Wilson, G.S.; Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand THE ANDRIL-SMS Science Team; http://www.andrill.org/projects/sms/team.html Geology Department, University of California – Davis, One Shields Ave., Davis, California, 95616 – USA Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand Dipartimento di Scienze della Terra, Università di Siena, Via del Laterino 8, I-53100 Siena – Italy http://www.andrill.org/projects/sms/team.html 2009 http://hdl.handle.net/2122/6033 en eng Terra Antartica Terra Antartica /15 (2009) Acton, G., Crampton, J., Di Vincenzo, G., Fielding, C.R., Florindo, F., Hannah, M., Harwood, D., Ishman, S., Johnson, K., Jovane, L., Levy, R., Lum, B., Marcano, C., Mukasa, S., Ohneiser, C., Olney, M., Riesselman, C., Sagnotti, L., Stefano, C., Strada, E., Taviani, M., Tuzzi, E., Verosub, K.L., Wilson, G.S., Zattin, M., and The ANDRILL-SMS Science Team, 2008-2009. Preliminary integrated chronostratigraphy of the AND-2A Core, ANDRILL Southern McMurdo Sound Project, Antarctica, Terra Antartica, 15, this volume, 211-220. Cande S.C. & Kent D.V., 1995. Revised calibration of the geomagnetic polarity timescale for the Late Cretaceous and Cenozoic. J. Geophys. Res., 100, 6093-6095. Fielding C.R., Atkins C.B., Bassett K.N., Browne G.H., Dunbar G.B., Field B.D., Frank T.D., Krissek L.A., Panter K.S., Passchier S., Pekar S.F., Sandroni S., Talarico F., & the ANDRILL-SMS Science Team, 2008. Sedimentology and Stratigraphy of the AND-2A Core. ANDRILL Southern McMurdo Sound Project, Antarctica. Terra Antartica, 15, this volume, 77-112. Fisher R.A., 1953. Dispersion on a sphere. Proc. R. Soc. London A, 217, 295-305. Gradstein F.M., Ogg J.G., & Smith A.G, 2004. A Geologic Time Scale 2004. Cambridge University Press, Cambridge, United Kingdom, 610 pp. Kirschvink J.L., 1980. The least-squares line and plane and the analysis of palaeomagnetic data. Geophys. J. R. Astron. Soc., 62, 699-718. Kretz R., 1983. Symbols for rock forming minerals. American Mineralogist, 68, 277-279. Panter K.S., Talarico F., Bassett K., Del Carlo P., Field B., Frank T., Hoffman S., Kuhn G., Reichelt L., Sandroni S., Taviani M., Bracciali L., Cornamusini G., von Eynatten, H., Rocchi S., & the ANDRILL-SMS Science Team, 2008-2009. Petrologic and geochemical composition of the AND-2A Core, ANDRILL, Southern McMurdo Sound Project, Antarctica. Terra Antartica, 15, this volume, 147-192. Turner G.M., 2001. Toward an understanding of the mulicomponent magnetization of uplifted Neogene marine sediments in New Zealand, J. Geophys. Res., 106, 6385-6397. Wessel P., & Smith W.H.F., 1998. New, improved version of the Generic Mapping Tools released. Eos Trans. AGU, 79, 579. Wilson G.S., Florindo F., Sagnotti L., Ohneiser C., & the ANDRILLMIS Science Team, 2007. Palaeomagnetism of the AND-1B Core, ANDRILL McMurdo Ice Shelf Project, Antarctica. Terra Antartica, 14, 289-296. Worm H.-U., 1998. On the superparamagnetic-stable single domain transition for magnetite, and frequency dependence of susceptibility. Geophys. J. Int., 133, 201-206. http://hdl.handle.net/2122/6033 restricted Magnetostratigraphy ANDRILL Antarctica Paleomagnetism 04. Solid Earth::04.04. Geology::04.04.10. Stratigraphy 04. Solid Earth::04.05. Geomagnetism::04.05.06. Paleomagnetism article 2009 ftingv 2022-07-29T06:05:37Z We conducted initial palaeomagnetic studies on cores from site AND-2A (77°45.488’S, 165°16.605’E, ~383.57 metres water depth). A total of 813 samples were collected that span from the top of the section down to the base at 1138.54 metres below sea floor (mbsf). Samples were collected every one or two metres down the core, with paired (pilot) samples being collected about every ten to twenty metres to allow us to assess the demagnetisation behaviour of the samples using either alternating field (AF) or thermal demagnetisation. With the exception of only a few intervals, AF demagnetisation was observed to resolve a characteristic remanent magnetisation (ChRM) as well or better than thermal demagnetisation. Thermal demagnetisation was particularly ineffective in many intervals owing to thermal alteration that was common above 500°C and was evident in some samples even at low temperatures. Above Lithostratigraphic Unit (LSU) 8 (436.18 mbsf), where lithologies are generally more coarse grained than lower in the section, resolving a ChRM is difficult and recent overprints or a drilling overprint are a concern. Within LSU 8 and below, most samples have a ChRM that can be resolved. The ChRM is most likely an original depositional magnetisation throughout most of this lower section, although orthogonal demagnetisation diagrams contain evidence that normal polarity overprinting affects some intervals. Based on 40Ar/39Ar dates and diatom datums, the magnetozones identified from the base of the hole up to ~266mbsf are consistent with spanning from either Chron C6n (18.748-19.772 Ma) or C6An.1n (20.040-20.213 Ma) up through Chron C5Br (15.160-15.974 Ma). Above this, intervals of constant polarity are isolated within longer stratigraphic intervals of uncertain polarity, making their correlation with the geomagnetic polarity timescale (GPTS) speculative and highly dependent on ages obtained from other dating methods. One exception is a reversed-to-normal polarity transition that occurs at ~31 mbsf and is interpreted to most ... Article in Journal/Newspaper Antarc* Antarctica McMurdo Sound Earth-Prints (Istituto Nazionale di Geofisica e Vulcanologia) McMurdo Sound |