It has evaporated leaving evaporites such as borax. During the course of time, thousands of miles of ice can move through valleys in the form of glaciers. Glacial erosion deepens, widens, and straightens their valleys often creating nearly vertical valley walls. With the much lower sea level during glaciations, glaciers with coastal access eroded their valleys much below current sea level. As sea level rose and glaciers melt during interglacials, these deeply eroded coastal valleys became flooded creating fjords.
Fjords are often many hundreds to over a thousand feet deep.
Hanging valleys are tributary valleys to adjacent larger valleys once occupied by a valley glacier. The hanging valley was occupied by a smaller glacier which did not as deeply erode the valley floor. Once the glaciers melt the tributary valley outlet into the main valley is left hanging high on the main valley wall. Some of the largest waterfalls plunge from hanging valleys. C. Cirques, Aretes and Horns Alpine glaciers erode mountain peaks to create spectacular angular mountain landscapes.