Before revision: Lowland alluvial plains American Bottom— Lowland alluvial plains form when there is deposition of sediment over a long period of time by one or more rivers coming from highland regions, and then are deposited in lowland regions for long periods of time.
After revision: Lowland alluvial plains Lowland alluvial plains form when there is deposition of sediment over a long period of time by one or more rivers coming from highland regions, and then are deposited in lowland regions for long periods of time.