Pressure ice

From Glossary of Meteorology

pressure ice

Sea ice (or river ice or lake ice) that has been deformed or altered by the lateral stresses of any combination of wind, water currents, tides, waves, and surf.

This may include ice pressed against the shore, or one piece of ice upon another. Its two major forms are rafted ice and tented ice, which, individually or in combinations, may form pressure ridges or hummocked ice.