Here's why:
* Isostasy: The Earth's crust floats on the denser mantle below. This is similar to how an iceberg floats in water. The crust is constantly seeking a balance, called isostasy.
* Erosion and Isostasy: When erosion removes material from the surface, the weight on the crust decreases. This imbalance causes the crust to rise, similar to how an iceberg rises higher in the water when some ice melts.
* Crustal Thickening: As the crust rises, it may become thicker as the underlying mantle material flows upwards to fill the void created by the erosion.
In summary, erosion leads to a decrease in weight, which in turn causes the crust to rise and potentially thicken to regain isostatic balance.
