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How do tributaries influence the location of a river channel in a valley?

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Snow-capped, rugged Atlas Mountains encircle a green valley with scattered trees, terraced fields, and a few small buildings in Morocco. — valley The rugged Atlas Mountains surround a valley in Morocco.

In the study of geology, tributaries play a significant role in shaping the configuration of a valley floor and the positioning of the main river channel.

The primary influence of a tributary on a river's location is through the influx of sediment load. When a tributary joins a main river, it introduces a significant amount of material into the system. This influx of load often forces the main river channel toward the opposite side of the valley floor. This phenomenon has been documented in various river systems, such as the upper Mississippi River valley, where the sediment contribution from tributaries dictates the river's lateral position within the valley.1

Additionally, in the context of glacial landscapes, the erosive power of a main trunk glacier compared to smaller tributary glaciers creates discordant junctions. Because the main valley is eroded more rapidly than the side valleys, the tributary valleys are often left as hanging valleys that join the main valley at elevations substantially higher than the valley floor.23