How Are Fjords Formed?
A fjord forms where a glacier cut a gorge below sea level and then backed off. The U-shaped valley left behind fills with seawater, forming a narrow inlet with very steep sides. As the glacier moved forward, it pushed rock and earth debris ahead of it. The glacier’s retreat deposits the debris at a point where the inlet meets the sea. Water at the mouth of the inlet is therefore shallow, whereas the deepest part of the fjord can be more than 1300 meters (close to one mile) deep. Most fjords formed during an ice age when sea level was much lower than it is today.
