Geology of Middlesex County
The Concord River
The Concord is a river that originates where the Sudbury River and the Assabet River join together, and it ends when it joins the Merrimack River, a length of about 15.5 miles, or 24.9 kilometers.
Flood basin of the Concord River
As you can see from these pictures, the Concord River has a very large flood basin, a very low gradient, and that the river meanders a lot, which means that this is an old river. There are also common features of an old river surrounding the Concord River, such as oxbows, meander scars, and much deposition. The meandering river travels slowly which is a characteristic of an old river as well.
The fact that the valley of the river is more U-shaped than V-shaped indicates that the valley was created thousands of years ago when the Laurentide Ice Sheet covered the area and was carved out by the glacier. After this, the river was formed and started to flow through the valley. If the valley were V-shaped, it would mean the valley was carved by the river. However, the valley is U-shaped so it has not been carved by the river. Therefore, the river was formed after glaciation thousands of years ago.
The fact that the valley of the river is more U-shaped than V-shaped indicates that the valley was created thousands of years ago when the Laurentide Ice Sheet covered the area and was carved out by the glacier. After this, the river was formed and started to flow through the valley. If the valley were V-shaped, it would mean the valley was carved by the river. However, the valley is U-shaped so it has not been carved by the river. Therefore, the river was formed after glaciation thousands of years ago.
