Jäämuodostuma

Jäämuodostuma refers to any geological feature or deposit created by the action of glaciers or ice sheets. These formations are found in areas that were once covered by ice during glacial periods. The immense weight and movement of glaciers carve, transport, and deposit vast amounts of rock and sediment, shaping the landscape significantly.

Common types of jäämuodostuma include moraines, which are ridges or mounds of till deposited at the edge or beneath a glacier. Drumlins are elongated hills formed by glacial ice acting on underlying unconsolidated till or ground moraine. Eskers are long, winding ridges of stratified sand and gravel, representing sediment deposited by meltwater streams flowing within, under, or upon a glacier. Kettle lakes are depressions left behind when a block of ice melts after being buried in glacial deposits. Fjords are long, narrow inlets with steep sides or cliffs, created by glacial erosion. Glacial erratics are large rocks or boulders that have been transported by a glacier from their original location. Understanding jäämuodostuma is crucial for reconstructing past climates and glacial extents, as well as for comprehending the geological history of many regions. They also influence soil types and groundwater resources in the present day.