14 DAY TRIAL // An image collected by photographer Bryce Hand on September 1 shows what could be dubbed a double valley in Glacier Bay, Alaska. The photo was taken from a cruise ship passing in front of the glacier, which allowed Hand a clear view of this interesting landscape feature.
The reason why these two valleys are superimposed on one another is very simple. Researchers say that they were formed in different ways, and at different times on the geological timescale. There are two main elements in this photo: the raw and stream-cut canyon shaped like the letter V and the glacially eroded valley shaped like an U.
The U-shaped valley at the top of the image was created by glaciation, which is to say it was carved from the mountain by advancing glaciers. As with all similar formations, the passing of vast volumes of ice has smoothed it extensively.
Conversely, the V-shaped valley below was cut by the stream that flows from the glacier. Since it was never exposed to glaciation periods, it exhibits none of the smoothness that characterizes the area above. Consequently, it appears to be rawer than the other region, USRA reports.