Syngenetic dynamic of permafrost of a polar desert solifluction lobe, Ward Hunt Island, Nunavut

Repeated freeze–thaw cycles on slopes trigger sorting and solifluction mass movements, while subsequent displacement of material modifies the geomorphology of slopes as well as permafrost dynamics. This study focuses on the geomorphology and the cryostratigraphy of a polar desert stone-banked solifl...

Full description

Saved in:

Bibliographic Details
Published in:	Arctic science Vol. 3; no. 2; pp. 301 - 319
Main Authors:	Verpaelst, Manuel, Fortier, Daniel, Kanevskiy, Mikhail, Paquette, Michel, Shur, Yuri
Format:	Journal Article
Language:	English
Published:	Ottawa Canadian Science Publishing NRC Research Press 01-06-2017 Canadian Science Publishing
Subjects:	Accretion Climate change cryostratigraphy Deserts Divers Fins Freeze thaw cycles Freeze-thawing Gels Geomorphology Global warming Gravel Ground ice Hydrology Ice Ice formation Lobes Morphology Permafrost polar desert Ridges Sediments Slopes Solifluction solifluction lobe syngenetic permafrost Thawing Canada Nunavut Territory Canada
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Repeated freeze–thaw cycles on slopes trigger sorting and solifluction mass movements, while subsequent displacement of material modifies the geomorphology of slopes as well as permafrost dynamics. This study focuses on the geomorphology and the cryostratigraphy of a polar desert stone-banked solifluction lobe with the objective to clarify the impact of slow mass movements on ground ice aggradation. The morphology of the solifluction lobe was characterized by peripheral ridges of coarse gravel, partially surrounding a depression filled with finer sediments saturated with water and covered by organics. Cryostratigraphic analysis demonstrated that the solifluction lobe’s formation led to the development of a syngenetic layer of permafrost with an ice content that varied according to the location in the lobe. The ice-rich cryofacies formed in the central depression of the lobe should act as a buffer to potential active layer deepening, slowing down its thawing, whereas the ice-poor cryofacies formed under the ridges is expected to thaw faster than the central depression under climate warming scenarios. Thawing of the ice-rich zone in the future will result in differential thaw subsidence between the ridges and the central depression of solifluction lobes, along with increased drainage through the ridges and subsequent changes in hydrology.
ISSN:	2368-7460 2368-7460
DOI:	10.1139/as-2016-0018