Lithogenic elements and isotopes in peat cores as markers of Holocene climate changes in the Mackenzie River valley

Regions: Gwich'in Settlement Area

Tags: contaminants, mercury, climate change, paleoclimatology, pollution

Principal Investigator: Outridge, Peter M (1)
Licence Number: 14137
Organization: Geological Survey of Canada
Licensed Year(s): 2007
Issued: Mar 27, 2007
Project Team: Professor Bill Shotyk (expertise in atmospheric metals in peat bogs, University of Heidelberg, Germany), Dr Charles Tarnocai (peat bog growth and climate change, Agriculture Canada), Tom Nornberg (field mechanic and electronics tech, University of Southern Denmark), Pat Roach (field assistant, DIAND (Yukon))

Objective(s): The objective of this research is to reconstruct climate change information as well as recent industrial mercury and lead pollution histories for Inuvik and the lower Mackenzie River valley.

Project Description: The objective of this research is to reconstruct climate change information as well as recent industrial mercury and lead pollution histories for Inuvik and the lower Mackenzie River valley.

To determine the above, a core sample of peat will be taken from a peat bog located near Inuvik, and analyzed for elements and dusts deposited from the air over the last 7,000 years.

The site will be accessed on foot from the Dempster Highway - there will be no vehicle access on site and no overnight field camps. Equipment will be minimal. A specialized motorized light-weight titanium corer made especially for use in permafrosted peat bogs will be used. Two 12 cm diameter cores about 5 metres long will be taken from the bog, and the holes filled in afterwards. The plan is to do the coring in May while the ground is still frozen, to minimize disturbance. The site has been previously used for international scientific peat growth studies. The bog will be cored by a field team led by Prof. W. Shotyk, a world-recognized leader in trace element studies in peat bogs. The cores will be transported in coolers back to the University of Heildelberg where they will be sectioned into 1 cm and 2 cm increments, dried and powdered. All analyses require specific laboratory expertise and will be carried out at Heidelberg (Germany) and certain Canadian labs. The core sections will be aged, and concentrations of a wide range of geogenic trace and major elements, and stable isotopes of carbon and oxygen, will be determined. Flux profiles of elements and isotopes will be interpreted in the light of previous paleoclimate studies using lake sediments and peat bogs, carried out in other regions.

A report outlining the study’s results and conclusions will be prepared in electronic and paper formats and lodged with the Aurora Research Institute. The researcher will also report to the Northern Contaminants Program and ArcticNET network, both of which have a network of local communications representatives whose job is to bring any relevant information from these sources to their communities.
Fieldwork will be conducted from May 01 to 31, 2007 at about 15 km south of Inuvik, several hundred metres off the Dempster Highway (68 degrees 19' N and 133 degrees 25' W).