Glaciation
Changes Made by Glaciers
What is a Glacier?
The Free Dictionary defines the word glacier as: A huge mass of ice slowly flowing over a land mass, formed from compacted snow in an area where snow accumulation exceeds melting and sublimation.
This just means all the snow did not melt over the summer, and more snow fell. This repeated until there was a very large lump of ice. This lump of ice moves across land. As the ice moves, it shapes the earth. This is glaciation.
A Glacier
Striations Left Behind By a Glacier
A "U" Shaped Valley Created By a Glacier
How Do Glaciers Move?
According to Planet Green, there are two types of glaciers: alpine glaciers, which are found at high altitudes and flow down the mountain, and ice sheets, which spread and may be formed from several smaller glaciers. A glacier is made up of many parts. The terminus is the front of a glacier and is always in the same place, if the glacier is stable. Other features include moulins, which carry melted water through the glacier; seracs, which are jagged blocks of ice that form when softer ice falls away from denser ice; and ogives, which are wave-like formations at the bottom of an icefall (a place where a glacier falls over a cliff).
Glaciers are the largest moving objects on Earth. They are so powerful that they affect the shape of the planet in Antarctica. They carve lakes, create dams for rivers and can pulverize rock formations. There's a good chance that your current landscape was shaped by glaciers. Glaciers move either through spreading or a basal slip. With spreading, the glacier expands outward after its own weight becomes too heavy, similar to what happens to heated cookie dough. In a basal slip, the glacier is stationed on a slope and pressure melts ice at the bottom, forming a thin layer of water. The loss of friction allows the glacier to "slip," or slide down the slope. Glaciers flow like rivers even though they are made of ice. The compressed ice layers are very flexible under pressure.
Glaciers are the largest moving objects on Earth. They are so powerful that they affect the shape of the planet in Antarctica. They carve lakes, create dams for rivers and can pulverize rock formations. There's a good chance that your current landscape was shaped by glaciers. Glaciers move either through spreading or a basal slip. With spreading, the glacier expands outward after its own weight becomes too heavy, similar to what happens to heated cookie dough. In a basal slip, the glacier is stationed on a slope and pressure melts ice at the bottom, forming a thin layer of water. The loss of friction allows the glacier to "slip," or slide down the slope. Glaciers flow like rivers even though they are made of ice. The compressed ice layers are very flexible under pressure.