Glacier Erosion. When Glaciers Roamed the Earth By Sara Hauf. Part 1: Glaciers.
When Glaciers Roamed the Earth
By Sara Hauf
Thousands to million years ago, large masses of ice called glaciers covered the earth. There are two types of glaciers: valley and continental glaciers. A valley glacier is a long narrow glacier that forms when snow and ice build up in a high mountain valley. Continental glaciers are glaciers that cover up much of a continent or large land. They cover 10% of the earth’s surface today.
Glacial movement is a major force of erosion. One major process is called abrasion.Abrasion is when tiny bits of particles called loess, is carried either by water or wind and scratches the surface of rocks or other hard surfaces. There are 3 types of erosion, Erosion by Water, Waves and Wind. These agents are the major sources of erosion, and together, they can even grind down whole mountains.
Glaciers and erosion work hand and hand to form different landforms on earth. Wind pushes out till and sediments called longshore drift to form long narrow “fingers” of land along the coastlines called spits. Spits are found many places along the coast of the United States, like Cape Cod or Long Island. Both were formed by Erosion, and now are homes for many people.
When land is eroded, it can form new places from the old places. One example is a drumlin. A drumlin is a low oval mound or hill consisted of glacial till shaped by past glacial action. When the drumlins flood, it creates a new formation called a drowned drumlin. The Boston Harbor Islands were formed that way. Glaciers have done so many things to our earth, and so we should thank them for the new land and homes they have formed for us, even if it happened thousands of years ago.
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