A submarine mountain ridge where there is more or less continuous volcanism as a result of sea-floor spreading along the ridge. A homogenous, solid material with a fixed composition, e.g. gold, quartz or iron pyrite. The surface form can vary from flat plains to terrain with hills and ridges, e.g. drumlins. Terminal moraines and marginal moraines are often formed around glaciers. Moraine material consists of sharp edged or angular fragments.
Moraine is Norway's most common type of superficial deposit.