Miocene Strata in CRP-1, Cape Roberts Project, Antarctica
Based on the alternation of diamicts with other clastic sedimentary facies, the predominantly lithified Miocene section of CRP-1 has been divided into lithostratigraphic Units 5 to 7, with Unit 5 further divided into 8 subunits and Unit 6 into 3. Petrological investigations of extraformational clast...
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Language: | English |
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1998
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ftunivsiena:oai:usiena-air.unisi.it:11365/40891 2024-02-11T09:56:02+01:00 Miocene Strata in CRP-1, Cape Roberts Project, Antarctica Robert C. Anderson J. Armienti P. Atkins C. Barrett P. Bohaty S. Bryce S. Claps M. Curran M. Davey F. J. De Santis L. Ehrmann W. Florindo F. Fielding C. Hambrey M. Hannah M. Harwood D. M. Henrys S. Hoelscher F. Howe J. A. Jarrard R. Kettler R. Kooyman S. Kopsch C. Krissek L. Lavelle M. Levac E. Niessen F. Passchier S. Paulsen T. Powell R. Pyne A. Rafat G. Raine I. J. Roberts A. P. Sagnotti L. SANDRONI, SONIA Scholz E. Simes J. Smellie J. Strong P. Tabecki M. TALARICO, FRANCO MARIA Taviani M. Verosub K. L. Villa, G. Webb P. N. Wilson G. S. Wilson T. Wise S. W. Wonik T. Woolfe K. Wrenn J. H. Robert, C. Anderson, J. Armienti, P. Atkins, C. Barrett, P. Bohaty, S. Bryce, S. Claps, M. Curran, M. Davey, F. J. De Santis, L. Ehrmann, W. Florindo, F. Fielding, C. Hambrey, M. Hannah, M. Harwood, D. M. Henrys, S. Hoelscher, F. Howe, J. A. Jarrard, R. Kettler, R. Kooyman, S. Kopsch, C. Krissek, L. Lavelle, M. Levac, E. Niessen, F. Passchier, S. Paulsen, T. Powell, R. Pyne, A. Rafat, G. Raine, I. J. Roberts, A. P. Sagnotti, L. Sandroni, Sonia Scholz, E. Simes, J. Smellie, J. Strong, P. Tabecki, M. Talarico, FRANCO MARIA Taviani, M. Verosub, K. L. Villa, G. Webb, P. N. Wilson, G. S. Wilson, T. Wise, S. W. 1998 STAMPA http://hdl.handle.net/11365/40891 eng eng volume:5 issue:1 firstpage:63 lastpage:124 numberofpages:62 journal:TERRA ANTARTICA http://hdl.handle.net/11365/40891 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0347468841 info:eu-repo/semantics/article 1998 ftunivsiena 2024-01-23T23:16:20Z Based on the alternation of diamicts with other clastic sedimentary facies, the predominantly lithified Miocene section of CRP-1 has been divided into lithostratigraphic Units 5 to 7, with Unit 5 further divided into 8 subunits and Unit 6 into 3. Petrological investigations of extraformational clasts indicate provenance from probable Cambro-Ordovician granites, metamorphic rocks (Koettlitz Group?), Ferrar dolerite and rhyolites of uncertain affinity. The sand fraction is dominated by grains derived from crystalline basement and the Beacon Supergroup, but volcanic glass, abundant above 62 mbsf, is correlated with the McMurdo Volcanic Group. X-ray diffraction analysis of mud samples shows a similar change in mineralogy over the interval 60-65 mbsf from smectite-dominated above to illite and chlorite-dominated below. The Miocene section is dated by diatom biostratigraphy at 17.5-22.4 Ma (early Miocene), which suggests an average sediment accumulation rate of about 21 m/my. The most prevalent fossil groups are diatoms, foraminifers and palynomorphs. The well-preserved marine palynomorph assemblage contains many new acritarchs, and apparently represents the first known palynomorph record from in situ lower-Miocene Antarctic sediments. Calcareous nannofossils (Thoracosphaera) are rare to few, as are macrofossils (serpulid worm tubes, echinoid spines, bryozoans, and scallop shells). Palaeoenvironmental interpretations suggest a glacimarine setting warmer than present that underwent some significant fluctuations in water depth and proximity to the ice margin. A magnetic-polarity stratigraphy has been measured for the lower c. 90 m. Four magnetozones defined below 89 mbsf are correlated within the range of Chrons C5Dr to C6 of the Magnetic Polarity Time Scale. The Miocene section has also been divided into six recurrent lithofacies: diamictite, rhythmically interlaminated finegrained sandstone and siltstone, well-stratified sandstone, poorly-stratified muddy sandstone, coarse-grained siltstone and fine-grained siltstone. ... Article in Journal/Newspaper Antarc* Antarctic Antarctica Università degli Studi di Siena: USiena air Antarctic Cape Roberts ENVELOPE(-70.467,-70.467,-68.950,-68.950) |
institution |
Open Polar |
collection |
Università degli Studi di Siena: USiena air |
op_collection_id |
ftunivsiena |
language |
English |
description |
Based on the alternation of diamicts with other clastic sedimentary facies, the predominantly lithified Miocene section of CRP-1 has been divided into lithostratigraphic Units 5 to 7, with Unit 5 further divided into 8 subunits and Unit 6 into 3. Petrological investigations of extraformational clasts indicate provenance from probable Cambro-Ordovician granites, metamorphic rocks (Koettlitz Group?), Ferrar dolerite and rhyolites of uncertain affinity. The sand fraction is dominated by grains derived from crystalline basement and the Beacon Supergroup, but volcanic glass, abundant above 62 mbsf, is correlated with the McMurdo Volcanic Group. X-ray diffraction analysis of mud samples shows a similar change in mineralogy over the interval 60-65 mbsf from smectite-dominated above to illite and chlorite-dominated below. The Miocene section is dated by diatom biostratigraphy at 17.5-22.4 Ma (early Miocene), which suggests an average sediment accumulation rate of about 21 m/my. The most prevalent fossil groups are diatoms, foraminifers and palynomorphs. The well-preserved marine palynomorph assemblage contains many new acritarchs, and apparently represents the first known palynomorph record from in situ lower-Miocene Antarctic sediments. Calcareous nannofossils (Thoracosphaera) are rare to few, as are macrofossils (serpulid worm tubes, echinoid spines, bryozoans, and scallop shells). Palaeoenvironmental interpretations suggest a glacimarine setting warmer than present that underwent some significant fluctuations in water depth and proximity to the ice margin. A magnetic-polarity stratigraphy has been measured for the lower c. 90 m. Four magnetozones defined below 89 mbsf are correlated within the range of Chrons C5Dr to C6 of the Magnetic Polarity Time Scale. The Miocene section has also been divided into six recurrent lithofacies: diamictite, rhythmically interlaminated finegrained sandstone and siltstone, well-stratified sandstone, poorly-stratified muddy sandstone, coarse-grained siltstone and fine-grained siltstone. ... |
author2 |
Robert, C. Anderson, J. Armienti, P. Atkins, C. Barrett, P. Bohaty, S. Bryce, S. Claps, M. Curran, M. Davey, F. J. De Santis, L. Ehrmann, W. Florindo, F. Fielding, C. Hambrey, M. Hannah, M. Harwood, D. M. Henrys, S. Hoelscher, F. Howe, J. A. Jarrard, R. Kettler, R. Kooyman, S. Kopsch, C. Krissek, L. Lavelle, M. Levac, E. Niessen, F. Passchier, S. Paulsen, T. Powell, R. Pyne, A. Rafat, G. Raine, I. J. Roberts, A. P. Sagnotti, L. Sandroni, Sonia Scholz, E. Simes, J. Smellie, J. Strong, P. Tabecki, M. Talarico, FRANCO MARIA Taviani, M. Verosub, K. L. Villa, G. Webb, P. N. Wilson, G. S. Wilson, T. Wise, S. W. |
format |
Article in Journal/Newspaper |
author |
Robert C. Anderson J. Armienti P. Atkins C. Barrett P. Bohaty S. Bryce S. Claps M. Curran M. Davey F. J. De Santis L. Ehrmann W. Florindo F. Fielding C. Hambrey M. Hannah M. Harwood D. M. Henrys S. Hoelscher F. Howe J. A. Jarrard R. Kettler R. Kooyman S. Kopsch C. Krissek L. Lavelle M. Levac E. Niessen F. Passchier S. Paulsen T. Powell R. Pyne A. Rafat G. Raine I. J. Roberts A. P. Sagnotti L. SANDRONI, SONIA Scholz E. Simes J. Smellie J. Strong P. Tabecki M. TALARICO, FRANCO MARIA Taviani M. Verosub K. L. Villa, G. Webb P. N. Wilson G. S. Wilson T. Wise S. W. Wonik T. Woolfe K. Wrenn J. H. |
spellingShingle |
Robert C. Anderson J. Armienti P. Atkins C. Barrett P. Bohaty S. Bryce S. Claps M. Curran M. Davey F. J. De Santis L. Ehrmann W. Florindo F. Fielding C. Hambrey M. Hannah M. Harwood D. M. Henrys S. Hoelscher F. Howe J. A. Jarrard R. Kettler R. Kooyman S. Kopsch C. Krissek L. Lavelle M. Levac E. Niessen F. Passchier S. Paulsen T. Powell R. Pyne A. Rafat G. Raine I. J. Roberts A. P. Sagnotti L. SANDRONI, SONIA Scholz E. Simes J. Smellie J. Strong P. Tabecki M. TALARICO, FRANCO MARIA Taviani M. Verosub K. L. Villa, G. Webb P. N. Wilson G. S. Wilson T. Wise S. W. Wonik T. Woolfe K. Wrenn J. H. Miocene Strata in CRP-1, Cape Roberts Project, Antarctica |
author_facet |
Robert C. Anderson J. Armienti P. Atkins C. Barrett P. Bohaty S. Bryce S. Claps M. Curran M. Davey F. J. De Santis L. Ehrmann W. Florindo F. Fielding C. Hambrey M. Hannah M. Harwood D. M. Henrys S. Hoelscher F. Howe J. A. Jarrard R. Kettler R. Kooyman S. Kopsch C. Krissek L. Lavelle M. Levac E. Niessen F. Passchier S. Paulsen T. Powell R. Pyne A. Rafat G. Raine I. J. Roberts A. P. Sagnotti L. SANDRONI, SONIA Scholz E. Simes J. Smellie J. Strong P. Tabecki M. TALARICO, FRANCO MARIA Taviani M. Verosub K. L. Villa, G. Webb P. N. Wilson G. S. Wilson T. Wise S. W. Wonik T. Woolfe K. Wrenn J. H. |
author_sort |
Robert C. |
title |
Miocene Strata in CRP-1, Cape Roberts Project, Antarctica |
title_short |
Miocene Strata in CRP-1, Cape Roberts Project, Antarctica |
title_full |
Miocene Strata in CRP-1, Cape Roberts Project, Antarctica |
title_fullStr |
Miocene Strata in CRP-1, Cape Roberts Project, Antarctica |
title_full_unstemmed |
Miocene Strata in CRP-1, Cape Roberts Project, Antarctica |
title_sort |
miocene strata in crp-1, cape roberts project, antarctica |
publishDate |
1998 |
url |
http://hdl.handle.net/11365/40891 |
long_lat |
ENVELOPE(-70.467,-70.467,-68.950,-68.950) |
geographic |
Antarctic Cape Roberts |
geographic_facet |
Antarctic Cape Roberts |
genre |
Antarc* Antarctic Antarctica |
genre_facet |
Antarc* Antarctic Antarctica |
op_relation |
volume:5 issue:1 firstpage:63 lastpage:124 numberofpages:62 journal:TERRA ANTARTICA http://hdl.handle.net/11365/40891 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0347468841 |
_version_ |
1790600185338920960 |