These authors examined the soils and waters near the Haughton crater on Devon Island, to determine the importance of chemical and mechanical weathering in this polar desert environment. They examined dissolved material in streams, lakes, snow, and groundwaters, and the size distribution, shape, and chemical composition of particles from soils in several different local landforms and parent materials.
Despite low temperatures, low precipitation, and very low vegetation presence, significant chemical weathering was found. Signs of chemical weathering, rather than mechanical, include rounded surfaces and pits in sand particles and the concentrations of Ca2+, Mg2+, and HCO3- in waters. Signs of mechanical weathering were also found, including sharp fracture lines in particles.
A gradient of increasing chemical weathering and decreasing mechanical weathering was found from the surface to the permafrost table. Thermal buffering reduces the frequency of frost-driven forces and thermal expansion from daily at the surface to annually at the permafrost table. The permafrost acts as a barrier to water movement, creating relatively wet condtions at depth that allow aqueous chemistry including the dissolution of dolomite to proceed.
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