Title | Late Quaternary sedimentation and permafrost development in a Svalbard fjord-valley, Norwegian high Arctic |
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Author | Gilbert, G L; O'Neill, H B ; Nemec, W; THiel, C; Christiansen, H H; Buylaert, J -P |
Source | Sedimentology 2018 p. 1-28, https://doi.org/10.1111/sed.12476 Open Access |
Image |  |
Year | 2018 |
Alt Series | Natural Resources Canada, Contribution Series 20180044 |
Publisher | Wiley-Blackwell |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Area | Spitsbergen; Adventdalen Fjord; Adventdalselva; Norway; Svalbard and Jan Mayen |
Lat/Long WENS | 15.0000 16.0000 78.5000 78.0000 |
Subjects | surficial geology/geomorphology; sedimentology; stratigraphy; geochronology; Nature and Environment; fiords; permafrost; ground ice; sedimentation; glacial deposits; tills; glaciomarine deposits;
deltaic deposits; eolian deposits; stratigraphic analyses; sedimentary facies; facies descriptions; core samples; radiometric dating; radiocarbon dating; mass spectrometer analysis; depositional history; glacial history; glaciation; deglaciation;
shoreline changes; sea level changes; climate; sedimentary structures; lithofacies; bioturbation; isostatic rebound; Last Glacial Maximum; Weichselian Glaciation; alluvial floodplain sediments; alluvial terraced sediments; Phanerozoic; Cenozoic;
Quaternary |
Illustrations | location maps; geoscientific sketch maps; photographs; tables; lithologic sections; profiles; schematic representations |
Program | Climate Change
Geoscience Permafrost |
Released | 2018 03 25 |
Abstract | The infilling history of the Adventdalen fjord-valley in central Spitsbergen is reconstructed, with a focus on permafrost development, based on sedimentological and cryostratigraphic evidence from
drilling cores. The techniques of optically stimulated luminescence and radiocarbon accelerator mass-spectrometry dating were used to establish sediment chronology. The fjord-fill sedimentary succession includes the fjord-bottom late Weichselian
subglacial till of the Last Glacial Maximum, the early Holocene muddy glaciomarine deposits with ice-rafted debris formed during the fjord deglaciation, and the younger Holocene deposits of a fjord-head Gilbert-type delta of which the fluvial
distributary plain shows raised alluvial terraces hosting aeolian sedimentation. This sedimentary record of the last glaciation/deglaciation cycle is interpreted in terms of sequence stratigraphy. Zones of epigenetic and syngenetic permafrost are
recognized from the vertical distribution of cryofacies, with a conclusion that the formation of permafrost commenced and extended down-fjord as the fluvio-deltaic fjord-fill was gradually reaching subaerial exposure. The upwards-grown syngenetic
permafrost and the top part of downwards-grown epigenetic permafrost below contain excess ice in a suite of cryofacies indicating ground-ice segregation and segregative intrusion. The deeper epigenetic permafrost is ice-poor and contains cryofacies
formed solely by segregation processes. This case study may serve as an analogue for other similar Arctic fjord-valleys where the fjord-head shoreline was established during the post-Weichselian deglaciation. |
Summary | (Plain Language Summary, not published) Sediment infilling and permafrost history of a fjord valley in central Spitsbergen were reconstructed. The sedimentary succession includes subglacial
till of the Last Glacial Maximum, muddy glaciomarine deposits formed during the fjord deglaciation, and the younger deposits of a fjord-head delta. Upward-grown syngenetic permafrost and the top part of downward-grown epigenetic permafrost below are
ice rich. This case study may serve as an analogue for other similar Arctic fjord-valleys. |
GEOSCAN ID | 308217 |
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