Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies
In 1973, DVDP 4 drilling was performed to obtain unconsolidated sediments of Lake Vanda, McMurdo Oasis. The cored sediments were found to contain layered salt concretions composed of gypsum, thenardite and calcite. On the basis of stable isotope compositions, δ^<13>C, δ^<18>O and δ^<3...
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National Institute of Polar Research
1977
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ftdoajarticles:oai:doaj.org/article:0fdeb9b320b045eda974681e76f5ffb6 2023-05-15T14:01:23+02:00 Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies Nobuyuki NAKAI Yoshihiko MIZUTANI 1977-03-01T00:00:00Z https://doi.org/10.15094/00007923 https://doaj.org/article/0fdeb9b320b045eda974681e76f5ffb6 EN JA eng jpn National Institute of Polar Research http://doi.org/10.15094/00007923 https://doaj.org/toc/0085-7289 https://doaj.org/toc/2432-079X doi:10.15094/00007923 0085-7289 2432-079X https://doaj.org/article/0fdeb9b320b045eda974681e76f5ffb6 Antarctic Record, Iss 58, Pp 244-253 (1977) Geography (General) G1-922 article 1977 ftdoajarticles https://doi.org/10.15094/00007923 2022-12-31T13:27:44Z In 1973, DVDP 4 drilling was performed to obtain unconsolidated sediments of Lake Vanda, McMurdo Oasis. The cored sediments were found to contain layered salt concretions composed of gypsum, thenardite and calcite. On the basis of stable isotope compositions, δ^<13>C, δ^<18>O and δ^<34>S, on the water and salts, it was concluded that the lake and the Wright Valley were once a fijord containing sea water and isolated from the ocean by glaciation. Micropaleontological studies for the cored sediments were also performed, indicating the existence of marine fossil fragments, marine sponge microsclere and marine centric diatom, only below the 1st gravel laver. This supports the above conclusions. In the 1975-1976 field survey season, layered mirabilite (or gypsum), ice and marine sediment, which were found under moraines at the height of 60 to 150 m above sea level near the coast of McMurdo Sound, have been studied on their occurrences and analyzed isotopically. These sulfate minerals and ice were found to be of marine in origin according to their isotopic compositions. This fact suggests that the sea water level largely fluctuated in geologic time and reached possibly 150 m higher than the present, and the present Wright Valley and Taylor Valley were under ocean water in the past. Article in Journal/Newspaper Antarc* Antarctica McMurdo Sound Directory of Open Access Journals: DOAJ Articles McMurdo Sound Taylor Valley ENVELOPE(163.000,163.000,-77.617,-77.617) Vanda ENVELOPE(161.550,161.550,-77.533,-77.533) Wright Valley ENVELOPE(161.833,161.833,-77.517,-77.517) Lake Vanda ENVELOPE(161.600,161.600,-77.517,-77.517) Laver ENVELOPE(20.250,20.250,65.767,65.767) |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English Japanese |
topic |
Geography (General) G1-922 |
spellingShingle |
Geography (General) G1-922 Nobuyuki NAKAI Yoshihiko MIZUTANI Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies |
topic_facet |
Geography (General) G1-922 |
description |
In 1973, DVDP 4 drilling was performed to obtain unconsolidated sediments of Lake Vanda, McMurdo Oasis. The cored sediments were found to contain layered salt concretions composed of gypsum, thenardite and calcite. On the basis of stable isotope compositions, δ^<13>C, δ^<18>O and δ^<34>S, on the water and salts, it was concluded that the lake and the Wright Valley were once a fijord containing sea water and isolated from the ocean by glaciation. Micropaleontological studies for the cored sediments were also performed, indicating the existence of marine fossil fragments, marine sponge microsclere and marine centric diatom, only below the 1st gravel laver. This supports the above conclusions. In the 1975-1976 field survey season, layered mirabilite (or gypsum), ice and marine sediment, which were found under moraines at the height of 60 to 150 m above sea level near the coast of McMurdo Sound, have been studied on their occurrences and analyzed isotopically. These sulfate minerals and ice were found to be of marine in origin according to their isotopic compositions. This fact suggests that the sea water level largely fluctuated in geologic time and reached possibly 150 m higher than the present, and the present Wright Valley and Taylor Valley were under ocean water in the past. |
format |
Article in Journal/Newspaper |
author |
Nobuyuki NAKAI Yoshihiko MIZUTANI |
author_facet |
Nobuyuki NAKAI Yoshihiko MIZUTANI |
author_sort |
Nobuyuki NAKAI |
title |
Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies |
title_short |
Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies |
title_full |
Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies |
title_fullStr |
Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies |
title_full_unstemmed |
Geological History of the Dry Valleys, Antarctica, Based on the Stable Isotope Studies |
title_sort |
geological history of the dry valleys, antarctica, based on the stable isotope studies |
publisher |
National Institute of Polar Research |
publishDate |
1977 |
url |
https://doi.org/10.15094/00007923 https://doaj.org/article/0fdeb9b320b045eda974681e76f5ffb6 |
long_lat |
ENVELOPE(163.000,163.000,-77.617,-77.617) ENVELOPE(161.550,161.550,-77.533,-77.533) ENVELOPE(161.833,161.833,-77.517,-77.517) ENVELOPE(161.600,161.600,-77.517,-77.517) ENVELOPE(20.250,20.250,65.767,65.767) |
geographic |
McMurdo Sound Taylor Valley Vanda Wright Valley Lake Vanda Laver |
geographic_facet |
McMurdo Sound Taylor Valley Vanda Wright Valley Lake Vanda Laver |
genre |
Antarc* Antarctica McMurdo Sound |
genre_facet |
Antarc* Antarctica McMurdo Sound |
op_source |
Antarctic Record, Iss 58, Pp 244-253 (1977) |
op_relation |
http://doi.org/10.15094/00007923 https://doaj.org/toc/0085-7289 https://doaj.org/toc/2432-079X doi:10.15094/00007923 0085-7289 2432-079X https://doaj.org/article/0fdeb9b320b045eda974681e76f5ffb6 |
op_doi |
https://doi.org/10.15094/00007923 |
_version_ |
1766271191151017984 |