jätma

Jäätma is a geological term referring to a landform created by glacial ice. These features are typically found in regions that were once covered by glaciers, such as parts of Scandinavia, North America, and the Alps. Glacial ice, due to its immense weight and slow movement, has the power to significantly alter the landscape. As glaciers advance and retreat, they erode bedrock and transport large amounts of sediment, known as glacial till.

When glaciers melt and recede, the deposited till can form various jäätma features. Common examples include moraines, which are ridges of unsorted debris deposited at the edges or base of a glacier. Drumlins are elongated, streamlined hills that are formed by the passage of glacial ice over unconsolidated till. Kettle lakes, or kettles, are depressions formed when a buried block of ice melts, leaving behind a hollow that can fill with water. Eskers are long, winding ridges of sand and gravel deposited by meltwater streams flowing within, under, or upon a glacier. These various landforms provide important clues about past glacial activity and the history of Earth's climate.