To identify the type of weathering illustrated in a rock from Whistler, Canada, we need to consider the common processes that lead to weathering in that region.
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A. Frost wedging: This occurs when water seeps into cracks in the rock and freezes, expanding and causing the rock to break apart. This is common in cold climates with freeze-thaw cycles, which is likely for Whistler.
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B. Abrasion: This is the wearing away of rock surfaces by friction or impact from other rock particles, often due to wind, water, or ice movement. While it can occur, it’s less specific to the conditions in Whistler.
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C. Pressure release: This occurs when overlying material is removed, reducing pressure on the underlying rock, and leading to cracking or flaking. It’s more typical in areas with significant geological uplift.
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D. Salt weathering: This happens when salt crystals form in rock pores or cracks, causing the rock to break apart. It’s more common in arid environments.
Given Whistler's cold climate, frost wedging (A) is the most likely type of weathering illustrated in the rock, as the repeated freeze-thaw cycles can lead to the fragmentation of the rock.
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