Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica
The bulk chemistry of mudrocks in Ross Sea drillcores on the Antarctic inner shelf is re-evaluated to extract records of continental paleotemperatures and ice extent. The chemical index of alteration (CIA) of the sedimentary sequence derived from the composite of the Cape Roberts cores changes in ac...
Published in: | Palaeogeography, Palaeoclimatology, Palaeoecology |
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Montclair State University Digital Commons
2008
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ftmontclairstuni:oai:digitalcommons.montclair.edu:earth-environ-studies-facpubs-1453 2023-07-23T04:14:30+02:00 Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica Passchier, Sandra Krissek, L. A. 2008-04-07T07:00:00Z https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/454 https://doi.org/10.1016/j.palaeo.2007.08.012 unknown Montclair State University Digital Commons https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/454 doi:10.1016/j.palaeo.2007.08.012 Department of Earth and Environmental Studies Faculty Scholarship and Creative Works Antarctica CIA Cenozoic Chemical weathering Continental text 2008 ftmontclairstuni https://doi.org/10.1016/j.palaeo.2007.08.012 2023-07-03T21:48:36Z The bulk chemistry of mudrocks in Ross Sea drillcores on the Antarctic inner shelf is re-evaluated to extract records of continental paleotemperatures and ice extent. The chemical index of alteration (CIA) of the sedimentary sequence derived from the composite of the Cape Roberts cores changes in accordance with pCO2 [Pagani, M., Zachos, J.C., Freeman, K.H., Tipple, B., Bohaty, S., 2005. Marked change in atmospheric carbon dioxide concentrations during the Paleogene, Science 309, 600-603]. The (K2O + Na2O)/Al2O3 molar ratio of the mudrocks is used as a mean summer temperature proxy for continental Antarctica and it shows similarities with benthic Mg/Ca temperatures for the Southern Ocean [Billups, K., Schrag, D.P., 2002. Paleotemperatures and ice-volume of the past 27 myr revisited with paired Mg/Ca and stable isotope measurements on benthic foraminifera. Paleoceanography 17. doi 10.1029/2000PA000567]. The ratio is calibrated using intervals with significant pollen assemblages and the temperature proxy enables extrapolation of the paleoclimatic data over a larger portion of the drilled record. The CIA and (K + Na)/Al ratios support a persistent cooling and drying of climate through the Oligocene-Miocene transition. The results reinforce the strong coupling between East Antarctic continental temperatures and ice volume, with deep-sea temperatures and concentrations of atmospheric carbon over long timescales. Text Antarc* Antarctic Antarctica Ross Sea Southern Ocean Montclair State University Digital Commons Antarctic Southern Ocean The Antarctic Ross Sea Cape Roberts ENVELOPE(-70.467,-70.467,-68.950,-68.950) Palaeogeography, Palaeoclimatology, Palaeoecology 260 1-2 30 40 |
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Montclair State University Digital Commons |
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ftmontclairstuni |
language |
unknown |
topic |
Antarctica CIA Cenozoic Chemical weathering Continental |
spellingShingle |
Antarctica CIA Cenozoic Chemical weathering Continental Passchier, Sandra Krissek, L. A. Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica |
topic_facet |
Antarctica CIA Cenozoic Chemical weathering Continental |
description |
The bulk chemistry of mudrocks in Ross Sea drillcores on the Antarctic inner shelf is re-evaluated to extract records of continental paleotemperatures and ice extent. The chemical index of alteration (CIA) of the sedimentary sequence derived from the composite of the Cape Roberts cores changes in accordance with pCO2 [Pagani, M., Zachos, J.C., Freeman, K.H., Tipple, B., Bohaty, S., 2005. Marked change in atmospheric carbon dioxide concentrations during the Paleogene, Science 309, 600-603]. The (K2O + Na2O)/Al2O3 molar ratio of the mudrocks is used as a mean summer temperature proxy for continental Antarctica and it shows similarities with benthic Mg/Ca temperatures for the Southern Ocean [Billups, K., Schrag, D.P., 2002. Paleotemperatures and ice-volume of the past 27 myr revisited with paired Mg/Ca and stable isotope measurements on benthic foraminifera. Paleoceanography 17. doi 10.1029/2000PA000567]. The ratio is calibrated using intervals with significant pollen assemblages and the temperature proxy enables extrapolation of the paleoclimatic data over a larger portion of the drilled record. The CIA and (K + Na)/Al ratios support a persistent cooling and drying of climate through the Oligocene-Miocene transition. The results reinforce the strong coupling between East Antarctic continental temperatures and ice volume, with deep-sea temperatures and concentrations of atmospheric carbon over long timescales. |
format |
Text |
author |
Passchier, Sandra Krissek, L. A. |
author_facet |
Passchier, Sandra Krissek, L. A. |
author_sort |
Passchier, Sandra |
title |
Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica |
title_short |
Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica |
title_full |
Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica |
title_fullStr |
Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica |
title_full_unstemmed |
Oligocene-Miocene Antarctic Continental Weathering Record and Paleoclimatic Implications, Cape Roberts Drilling Project, Ross Sea, Antarctica |
title_sort |
oligocene-miocene antarctic continental weathering record and paleoclimatic implications, cape roberts drilling project, ross sea, antarctica |
publisher |
Montclair State University Digital Commons |
publishDate |
2008 |
url |
https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/454 https://doi.org/10.1016/j.palaeo.2007.08.012 |
long_lat |
ENVELOPE(-70.467,-70.467,-68.950,-68.950) |
geographic |
Antarctic Southern Ocean The Antarctic Ross Sea Cape Roberts |
geographic_facet |
Antarctic Southern Ocean The Antarctic Ross Sea Cape Roberts |
genre |
Antarc* Antarctic Antarctica Ross Sea Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica Ross Sea Southern Ocean |
op_source |
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works |
op_relation |
https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/454 doi:10.1016/j.palaeo.2007.08.012 |
op_doi |
https://doi.org/10.1016/j.palaeo.2007.08.012 |
container_title |
Palaeogeography, Palaeoclimatology, Palaeoecology |
container_volume |
260 |
container_issue |
1-2 |
container_start_page |
30 |
op_container_end_page |
40 |
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1772185220670291968 |