very quickly and has a lot of power. The river can cut deep gorges and v-shaped valleys in the softer rocks. In the harder rocks they can form waterfalls. The river moves rocks and pebbles along its bed by bouncing and rolling. The lighter sediments are carried or dissolved in the water. When they reach the more gentle slopes the river becomes wider and moves slower. Mud and sand is dropped when the river floods and forms ridges along the river bank. When the river reaches the low plains it begins to meander.