| _version_ | 1867170465108197376 |
|---|---|
| author | Fritz, Michael Wetterich, Sebastian Meyer, Hanno Schirrmeister, Lutz Lantuit, Hugues Pollard, Wayne H |
| author_facet | Fritz, Michael Wetterich, Sebastian Meyer, Hanno Schirrmeister, Lutz Lantuit, Hugues Pollard, Wayne H |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Herschel Island in the southern Beaufort Sea is a push moraine at the northwestern-most limit of the Laurentide Ice Sheet. Stable water isotope (d18O, dD) and hydrochemical studies were applied to two tabular massive ground ice bodies to unravel their genetic origin. Buried glacier ice or basal regelation ice was encountered beneath an ice-rich diamicton with strong glaciotectonic deformation structures. The massive ice isotopic composition was highly depleted in heavy isotopes (mean d18O: -33 per mil; mean dD: -258 per mil), suggesting full-glacial conditions during ice formation. Other massive ice of unknown origin with a very large d18O range (from -39 to -21 per mil) was found adjacent to large, striated boulders. A clear freezing slope was present with progressive depletion in heavy isotopes towards the centre of the ice body. Fractionation must have taken place during closed-system freezing, possibly of a glacial meltwater pond. Both massive ground ice bodies exhibited a mixed ion composition suggestive of terrestrial waters with a marine influence. Hydrochemical signatures resemble the Herschel Island sediments that are derived from nearshore marine deposits upthrust by the Laurentide ice. A prolonged contact between water feeding the ice bodies and the surrounding sediment is therefore inferred. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_809946 |
| institution | PANGAEA |
| language | en |
| publishDate | 2011 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Isotopic ratios and ion composition of massive ground ice on Herschel Island Fritz, Michael Wetterich, Sebastian Meyer, Hanno Schirrmeister, Lutz Lantuit, Hugues Pollard, Wayne H AWI_PerDyn; International Polar Year (2007-2008); IPY; Permafrost Research (Periglacial Dynamics) @ AWI Herschel Island in the southern Beaufort Sea is a push moraine at the northwestern-most limit of the Laurentide Ice Sheet. Stable water isotope (d18O, dD) and hydrochemical studies were applied to two tabular massive ground ice bodies to unravel their genetic origin. Buried glacier ice or basal regelation ice was encountered beneath an ice-rich diamicton with strong glaciotectonic deformation structures. The massive ice isotopic composition was highly depleted in heavy isotopes (mean d18O: -33 per mil; mean dD: -258 per mil), suggesting full-glacial conditions during ice formation. Other massive ice of unknown origin with a very large d18O range (from -39 to -21 per mil) was found adjacent to large, striated boulders. A clear freezing slope was present with progressive depletion in heavy isotopes towards the centre of the ice body. Fractionation must have taken place during closed-system freezing, possibly of a glacial meltwater pond. Both massive ground ice bodies exhibited a mixed ion composition suggestive of terrestrial waters with a marine influence. Hydrochemical signatures resemble the Herschel Island sediments that are derived from nearshore marine deposits upthrust by the Laurentide ice. A prolonged contact between water feeding the ice bodies and the surrounding sediment is therefore inferred. |
| title | Isotopic ratios and ion composition of massive ground ice on Herschel Island |
| topic | AWI_PerDyn; International Polar Year (2007-2008); IPY; Permafrost Research (Periglacial Dynamics) @ AWI |
| url | https://doi.org/10.1594/PANGAEA.809946 |