foreland basin

/ fôr′lənd /

1. A low-lying region that is adjacent and parallel to a mountain belt formed as the result of the collision of tectonic plates. Foreland basins form when the lithosphere flexes downward in front of a mountain belt in response to the added load of thickened crust that results from the collision of the two plates. Sediments eroded from the mountain belt accumulate in the foreland basin, causing it to further subside and make room for additional sediments.