Match the vocabulary with the definition permanently frozen soil cavern of or near an ocean or sea maritime of or caused by the movement of the earth from the shifting of tectonic plates permafrost an underground area usually created when limestone is dissolved seismic a depression in the land generally caused when rain dissolves limestone soils sinkhole a large wave caused by an underwater earthquake or volcano tsunami

, permafrost is ground, including rock or (cryonic) soil, at or below the freezing point of water 0 °C (32 °F) for two or more years. Most permafrost is located in high latitudes (in and around the Arctic and Antarctic regions), but at lower latitudes alpine permafrost occurs at higher elevations. Ground ice is not always present, as may be in the case of non-porous bedrock, but it frequently occurs and it may be in amounts exceeding the potential hydraulic saturation of the ground material.