Base de données de recherche des TNO

Régions: Inuvialuit Settlement Region

étiquettes: permafrost, glaciology, fossils, paleoclimatology, paleohydrology, historical data, paleontology, flooding, biological productivity, topography, geomorphological processes, sediment core sampling

Objectif(s): The research team will obtain sediment cores from a series of lakes near Reindeer Station and in the Inuvik region for the purpose of reconstructing the hydrological, climatological and geomorphic history of the lower Mackenzie River basin. Lakes adjacent to the Mackenzie River floodplain are likely to be periodically inundated by flooding, and therefore contain sedimentary records of flood history. Several such lakes exist in the vicinity of Reindeer Station, NWT, and sediment cores taken from these lakes should provide robust records of past flooding events. Radiocarbon dating will be used to date flood event beds in the sedimentary records from these lakes, allowing reconstruction of the flood history of the Mackenzie River for the past thousand years or more. Sediment cores from higher elevation lakes on the bluffs to the east of Reindeer Station will be used as controls to provide long-term climatic histories that can be used to refine and isolate the flood signal in the lower lakes, as well as reconstruct landscape stability with reference to permafrost. By looking at lakes, as well as analysing changes in fossil biological remains and lake productivity, it is possible to identify changes in past landscape stability as well as determine how these changes are related to regional climate and permafrost. These results can also be used to remove the climate signal in the lower lake records and isolate the flood signal with greater precision, as well as identify the effects of long-term changes in past climate on flood frequency. Coring of several lakes in the Inuvik region will also help our understanding of the past climate and glacial history of the area.

Description du projet: The research team will obtain sediment cores from a series of lakes near Reindeer Station and Inuvik for the purpose of reconstructing the hydrological, climatological and geomorphic history of the lower Mackenzie River basin. The research will require fieldwork between 15 April and 25 April. Research will involve the development of a high-resolution paleoenvironmental record based on lake sediments from up to nine lakes in the Inuvialuit and Gwich'in Settlement Areas. Transportation in the field for the study will be by snowmobile and snowshoes. If snow cover is insufficient, transport will be by foot. The lake sediments will be accessed by use of an ice auger. Sediment coring will be carried out using a vibacorer powered by a 5.5 h.p. gasoline engine. Once collected, the sediment cores will be returned to the laboratory for detailed analysis. This work will increase our understanding of the effects of the North Atlantic and Arctic Ocean circulation on Arctic climate during the last 13,000-16,000 years.