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This picture captures the intricate dance of alpine processes beautifully.
The timescales of those processes all overlap to put them in meaningful order. Uplift happens both gradually over time and suddenly when near-surface faults slip. In high mountain ranges, the rate of uplift is often on the same order of magnitude as the average rate of erosion. Mineralization can be slow, as with deep intrusive igneous rocks, or fast, as with the growth of bones and shells. Erosion can be anything from the slow decomposition of minerals by lichens or dissolution by groundwater to the catastrophic destruction of levees during a flood. Soil formation is tied to both chemical and physical erosion.
Those piles of rubble represent the gradual accumulation over thousands of years of rocks and boulders that suddenly broke free and tumbled noisily down from the cliffs. The overall rate of erosion is related to slope angles, climate, and rock type. the steeper slopes found in mountain ranges allow faster streams, which erode more quickly than the slow, meandering streams of the flatlands. This erosion in turn makes the valley walls steeper and less stable, so begin to erode more quickly until the two reach a sort of equilibrium. The mountains grow taller where ever uplift is more rapid than erosion, and shorter where erosion out-paces uplift. Plants and humans fight erosion by stabilizing soil, but plants also accelerate erosion by forcing their roots into cracks in the rock.