Which primary mechanism influences fjord formation when glacial ice retreats from a coastal valley?

💡 Explanation

When glacial ice retreats, isostatic rebound occurs because the removal of the immense ice load allows the Earth's crust to slowly rise, flooding the U-shaped valley carved by the glacier and creating a fjord. Isostatic rebound defines fjords, rather than runoff, tectonics or weathering which affects general valleys at different scales.

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