Which best describes how wedge basins form? When two plates move apart, the weaker part of Earth’s crust moves down at normal faults where sediments are deposited until a basin forms. At the area where two bent plates slide past each other, a depression forms where sediments are deposited. When two plates collide, the non-subducting plate scrapes the subducting plate and forms a depression where sediments gather. At the area of a depression between two plates, sediments continue to get deposited and become compacted.