Clay Mineralogy and Morphology of Soils at Thor Lake, N.W.T., Canada

Abstract

<p>Investigation of the morphology and mineralogy of a group of soils in the southern part of the District of Mackenzie, N.W.T is reported. A uniform suite of clay-size minerals, reflecting locally reported bedrock, is observed with weathering of surface horizons resulting in the formation of vermiculite and montmorillonite from illite and chlorite. Kaolinite, attributed to pre-glacial formation, is illuviated downwards in the these soils. Considerable quartz, feldspar, hornblende and anatase are also noted in the <2 micron fraction. Dominant soil types are Humo-Ferric Podzols and Degraded Dystric Brunisols. It is proposed that the use of Degraded Brunisol for these soils in inappropriate. The nature of fragic and placic soil horizons in the area is>discussed.</p>