Ice river

Subglacial channels on the glacier melt away the glacier, creating huge caves, or tunnels, whose tops collapse to form deep, large, strip lakes.
One is the accumulation of water in the glacier depression, which is formed by strong melting erosion in summer. In addition, the jagged peaks around the glacier are constantly caving down debris.
If larger chunks of rock cover a glacier, causing differential melting, they can grow into ice mushrooms of varying sizes. Ice cups form quickly, forming large and small pools of water on the ice. During the summer melt, the temperature of water on the ice is very high, sometimes reaching 5℃.