Final answer:
Weathering on Earth can extend to hundreds of meters below the surface but is typically limited to the upper layers of the crust where atmospheric and biological factors influence the process.
Step-by-step explanation:
Weathering processes typically affect Earth's surface and can reach as far as hundreds of meters below the surface. Beyond a few kilometers, the Earth's crust becomes less affected by weathering due to the lack of exposure to atmospheric conditions and biological activity that drive most weathering processes. The mantle, which begins at the base of the crust and extends to a depth of 2900 kilometers, is not significantly affected by weathering because it is shielded by the crust and exposed to very high temperatures and pressures that prevent typical weathering.