Jäänauva

Jäänauva is a Finnish term referring to a type of glacial landform. It is essentially a moraine, which is a geological deposit of unconsolidated debris left behind by a glacier. Specifically, jäänauva can describe a ridge-like accumulation of glacial till that forms at the terminus of a glacier, or along its sides. These formations are created as the ice moves, pushing, carrying, and depositing rock and soil fragments.

The size and shape of a jäänauva can vary greatly depending on the amount of debris available to the glacier and the glacier's activity. Some jäänauvat are small and indistinct, while others can form substantial ridges stretching for kilometers. They are often composed of a mixture of sand, gravel, clay, and larger rocks. In certain contexts, the term might also refer to a series of smaller, elongated hummocks or ridges, sometimes called drumlins or crag and tail features, which are also glacial depositional landforms.

The study of jäänauva and other morainic features is important in glaciology and geomorphology, as they provide valuable clues about past glacial extent, ice flow dynamics, and the erosional and depositional processes that shaped landscapes. These landforms are common in areas that were once covered by ice sheets, such as Scandinavia, North America, and parts of Asia.