Question

What is unloading? How does it contribute to weathering?

Answer 1

If weathering refers to wearing down something by battering it with weather such as intense or long term rain, snow, ice, sun and cycling it round, then I'd wonder whether "unloading" is when there are intense amounts of an extreme weather. "Unloading" suggests a "dump" rather than a gradual thing.
On the other hand, as something is weathered, the bits that get worn off it must go somewhere. So maybe that's what the word "unloading" refers to.
In other words, I don't know.
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