Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica
Vestfjella (73-74°S, 13-16°W) is a 130 km long nunatak range in western Dronning Maud Land in East Antarctica, and its northern and southern ends are situated close to the present ice sheet grounding-line. Striations and lodgement till on nunatak Basen indicate that the northernmost Vestfjella nunat...
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| Format: | Article |
| Language: | English |
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Geological Society of Finland
1996-06-01
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| Series: | Bulletin of the Geological Society of Finland |
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| Online Access: | http://www.geologinenseura.fi/bulletin/Volume68/sgs_bt_068_1_pages_085_098.pdf |
| _version_ | 1818147163286274048 |
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| author | P. Lintinen |
| author_facet | P. Lintinen |
| author_sort | P. Lintinen |
| collection | DOAJ |
| description | Vestfjella (73-74°S, 13-16°W) is a 130 km long nunatak range in western Dronning Maud Land in East Antarctica, and its northern and southern ends are situated close to the present ice sheet grounding-line. Striations and lodgement till on nunatak Basen indicate that the northernmost Vestfjella nunataks were formerly covered by a thicker Antarctic ice sheet. Striations on the summit ridge of nunatak Plogen indicate that the minimum change in ice thickness has been 700 m at the present ice sheet grounding-line. The relatively uniform oldest striation direction on different nunatak summits and the altitude of Plogen, which is less than 200 m lower than the highest Vestfjella summits, indicates that the whole of Vestfjella may have been covered by an ice sheet. Oxidation of till surface stones and an increased clay fraction in the upper part of the till layer were the only indications of soil formation on Basen. The unweathered nature of the Basen lodgement till indicate a relatively young age for deglaciation. This conclusion is also supported by age determinations and sedimentological data obtained from Weddell Sea sediments by Norwegian researchers, suggesting that a grounded ice sheet extended to the shelf edge at around 21 ka B.P. However the age of the glaciation which covered Basen and Plogen and the subsequent deglaciation is not based on precise dates and therefore the late Wisconsinan/Veichselian age is only a working hypothesis. |
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| format | Article |
| id | doaj.art-e1b42bb400984e49afcabc212bb5d5b3 |
| institution | Directory Open Access Journal |
| issn | 0367-5211 1799-4632 |
| language | English |
| last_indexed | 2024-12-11T12:30:53Z |
| publishDate | 1996-06-01 |
| publisher | Geological Society of Finland |
| record_format | Article |
| series | Bulletin of the Geological Society of Finland |
| spelling | doaj.art-e1b42bb400984e49afcabc212bb5d5b32022-12-22T01:07:15ZengGeological Society of FinlandBulletin of the Geological Society of Finland0367-52111799-46321996-06-01681859810.17741/bgsf/68.1.007Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, AntarcticaP. LintinenVestfjella (73-74°S, 13-16°W) is a 130 km long nunatak range in western Dronning Maud Land in East Antarctica, and its northern and southern ends are situated close to the present ice sheet grounding-line. Striations and lodgement till on nunatak Basen indicate that the northernmost Vestfjella nunataks were formerly covered by a thicker Antarctic ice sheet. Striations on the summit ridge of nunatak Plogen indicate that the minimum change in ice thickness has been 700 m at the present ice sheet grounding-line. The relatively uniform oldest striation direction on different nunatak summits and the altitude of Plogen, which is less than 200 m lower than the highest Vestfjella summits, indicates that the whole of Vestfjella may have been covered by an ice sheet. Oxidation of till surface stones and an increased clay fraction in the upper part of the till layer were the only indications of soil formation on Basen. The unweathered nature of the Basen lodgement till indicate a relatively young age for deglaciation. This conclusion is also supported by age determinations and sedimentological data obtained from Weddell Sea sediments by Norwegian researchers, suggesting that a grounded ice sheet extended to the shelf edge at around 21 ka B.P. However the age of the glaciation which covered Basen and Plogen and the subsequent deglaciation is not based on precise dates and therefore the late Wisconsinan/Veichselian age is only a working hypothesis.http://www.geologinenseura.fi/bulletin/Volume68/sgs_bt_068_1_pages_085_098.pdfglacial geologyice sheetnunatakstillfabricmineral compositionstriationsQuaternaryVestfjellaDronning Maud LandAntarctica |
| spellingShingle | P. Lintinen Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica Bulletin of the Geological Society of Finland glacial geology ice sheet nunataks till fabric mineral composition striations Quaternary Vestfjella Dronning Maud Land Antarctica |
| title | Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica |
| title_full | Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica |
| title_fullStr | Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica |
| title_full_unstemmed | Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica |
| title_short | Evidence for the former existence of a thicker ice sheet on the Vestfjella nunataks in western Dronning Maud Land, Antarctica |
| title_sort | evidence for the former existence of a thicker ice sheet on the vestfjella nunataks in western dronning maud land antarctica |
| topic | glacial geology ice sheet nunataks till fabric mineral composition striations Quaternary Vestfjella Dronning Maud Land Antarctica |
| url | http://www.geologinenseura.fi/bulletin/Volume68/sgs_bt_068_1_pages_085_098.pdf |
| work_keys_str_mv | AT plintinen evidencefortheformerexistenceofathickericesheetonthevestfjellanunataksinwesterndronningmaudlandantarctica |