ISSN:
1437-3262
Keywords:
Beaufort Sea Mackenzie Delta Thermokarst lake Embayment Arctic Cesium radiocarbon Geochemistry Permafrost Acoustic stratigraphy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract. A multidisciplinary study was made of lakes and lagoons in a thermokarst embayment on Richards Island, Canadian Beaufort Sea, in order to investigate the response of the Mackenzie Delta shoreline to changing hydrological influences. Seismo-acoustic profiles made from an amphibious vehicle, combined with sediment core data, show that the deepest lakes contain up to 10 m of transparent or stratified silty mud overlying the Kittigazuit sand basement. Palynological and microfossil data from 21 surface samples allow delineation of freshwater, saltmarsh, tidal flat and subtidal assemblages. These modern reference data allow distinction of freshwater and marine facies in the cores and subsequent interpretation of geochemical content (carbon, ammonia, sulphate). Radiocarbon dates and 137 Cs show that sedimentation rates have increased by an order of magnitude since drowning of the embayment during the past millennium, and that most of this sediment is from the Mackenzie River plume.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s005310000126
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