Stamukha

A stamukha (plural: stamukhi) is a grounded accumulation of sea ice rubble that typically develops along the boundary between fast ice and the drifting pack ice, or becomes incorporated into the fast ice. It is a pressure ridge. Wind, currents and tides contribute to this phenomenon. Stamukhi tend to occur in belts that are parallel to the shoreline, along coastal shoals, at water depths of about 20 m (65 ft), but that can reach 50 m (160 ft). They can build up to heights 10 metres (33 ft) or more above the waterline. Although they remain pinned to the seabed, these features can be subject to small displacements, either due to thermal expansion or to the pressure exerted by the drifting pack ice onto the fast ice. Because stamukhi tend to be deeply grounded, they may occur as isolated ice features in the open sea during the summer season, after the surrounding ice has melted away.