composed primarily of elevated landform sea ice sea ice hummock 2019-01-31T19:11:58Z envoPolar Sea ice hummocks may be fresh or weathered. The weathering of hummocks is similar to young mountain peaks with steep slopes that erode into smooth, rolling hills, in this case during the summer melt season. The submerged volume of broken ice under the hummock, forced downwards by pressure, is termed a bummock. An elevation which is formed by pressure at the point of contact between ice floes, resulting in a conglomeration of broken ice. surface landform cryoform