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Transcript of Mount Rushmore
Release of pressure
The roots of the plants at the bottom of Mount Rushmore can go into the cracks and expand them.
We are not entirely sure if this is present in Mount Rushmore, but it is assumed it is.
Certain animals dig holes in the ground that can expose underlying rocks to the effects of weathering. These holes allow water and other mechanical weathering agents to reach the previously covered rocks, but because Mount Rushmore is a tourist attraction, this doesn't happen much.
The daily heating and cooling of rock, causes stress along the boundaries of various minerals that compose the rock. The reason for this is that different minerals expand and contract at different rates based on the temperature and composition. This is most definitely present in Mount Rushmore, as it is in the sun.
The Idaho Museum of Natural History describes the effects of frost action by explaining that water, as it trickles into fractures and pores of the rock, freezes as temperatures drop. Because water expands when it freezes, it makes the cracks bigger. This is also present in Mount Rushmore.
When there is less pressure on a rock, layers that are not firmly joined together peel off. The way pressure is released from the surface of the rock is by the removing of dirt. This is evident in Mount Rushmore.
Sand and other rock particles that are carried by wind,water, or ice can wear away exposed rock surfaces like sandpaper on wood. This is evident in Mount Rushmore.
Mount Rushmore is a rock. Because it is a rock, it is effected by almost all types of weathering, which is clearly evident in all of the pictures of it, although it might not be very evident because humans had shaped the rock, and some things, like this might have been intentional
Huh, a thinking bubble
I'm Thomas Jefferson!!!!
I'm not only the first president, but also the first here!
In the past, Mount Rushmore weathering was caused by kids who threw threw rocks at it (for their own sick enjoyment) and from the rain. In the present, weathering is caused by kids and cars that drove by, which caused pollution. The pollution caused acid rain, which then caused weathering. In the future, kids will still throw rocks, but cars will be more energy efficient, and cause less pollution.
In general, oxidation is when an atom or ion loses one or more electrons. A prime example is when iron rusts. In weathering, when oxygen combines with another substances, oxidation has occurred. This is mot present in Mount Rushmore because it is not made of a material that rusts.
Some minerals react with water and acid to take up hydrogen. This process is called hydration. One of example of this is Feldspar. Feldspar tends to hydrate and change to clay. This is not present on Mount Rushmore because the rock that Mount Rushmore was built with does not react to water in this way.
When carbon dioxide in the air dissolves in rain, a weak carbonic acid is formed. This weak acid, while harmless to plants and animals, is able to dissolve some kinds of rocks, such as feldspar and limestone in a process called carbonation. Carbonation seems to only make a noticeable difference in weak rocks, but I'm sure carbonation still affects Mount Rushmore.
This is a process by which minerals in the rocks dissolve directly in water. This is not evident in Mount Rushmore, because it isn't that type of rock.
Hydrolysis is a chemical reaction caused by water. Water changes the chemical composition and size of minerals in rock, making them less resistant to weathering. This is not evident in Mount Rushmore