Assessment of Aqueous Methogenic Precursor Compounds in Periglacial Groundwaters

Regions: Gwich'in Settlement Area

Tags: physical sciences, soil, biogeochemistry, limestone

Principal Investigator: Marschner, Mark (1)
Licence Number: 13432
Organization: University of Ottawa
Licenced Year(s): 2003
Issued: May 28, 2003
Project Team: Ian Clark

Objective(s): This study aims to better understand the formation of "calcrete" deposits, using field samples from the Campbell Uplift. Limestone fissures of the Campbell Uplift and surrounding region contain layered carbonate calcrete deposits formed by a direct involvement of methanogenic bacteria. During their emplacement in the recent geologic past, dissolved organic matter (DOM) from overlying soil horizons was an important source of nutrition for the organisms living within limestone fissures. To understand how the calcretes were formed, the composition of DOM needs to be assessed quantitatively and qualitatively. From laboratory-based incubation experiments using natural bacterial communities, it is known that carbon isotopes are significantly fractionated from one compound to another. Since the researcher's facilities now include instruments that can separate and collect organic matter fractions, they would like to process field samples from the overlying soil in the Campbell Uplift limestone terrain.