A narrow gap through a mountain range is called a mountain pass. These passes are also sometimes known as gaps, saddles, and cols.
A long narrow chain of hills and mountains is called a mountain range or a mountain chain.
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An alluvial fan is typically formed at the base of a mountain or hilly area where a river or stream exits a narrow canyon or valley, and the water carrying sediments spreads out onto a flatter, open area. The fan shape is created as the water slows down and deposits the sediment it was carrying.
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Alluvial fans are fan-shaped deposits of sediment that form at the base of a mountain where a stream or river exits a narrow canyon and spreads out onto a flat plain. They are typically composed of coarser material like gravel and sand near the mountain and finer material like silt and clay towards the outer edges. Alluvial fans can range in size from small, ephemeral features to large, well-developed landforms.
Besides deltas and placer deposits, stream deposits can also lead to the formation of alluvial fans and floodplains. Alluvial fans occur where a stream flows out of a narrow canyon into a wider area, depositing sediment in a fan-shaped pattern. Floodplains are flat areas adjacent to rivers that become covered with sediment during flood events, enriching the soil for agriculture. These features contribute to the shaping of landscapes and ecosystems.
A row or chain of mountains ranged in a line is called a mountain range. A narrow gap through a mountain range is a mountain pass.
An alluvial fan forms when a stream or river loses energy as it flows from a narrow valley onto a broader, flatter area, typically at the base of a mountain or hill. As the water slows down, it deposits sediment it carried, creating a fan-shaped, sloping accumulation of materials. Over time, these deposits build up, creating a distinct landform characterized by a wide, gently sloping surface. The process can be influenced by factors such as changes in water flow, sediment supply, and climatic conditions.
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A row or chain of mountains ranged in a line is called a mountain range. A narrow gap through a mountain range is a mountain pass.
A five-letter word for "narrow mountain stream" is "brook".