The following activity will help you become familiar with some amazing landforms. You may have had an opportunity to visit them and if not you might not even be aware that they exist. As you go throughout this course, you should start understanding the concepts behind the formation of these landforms.
Click on the link below to see some of the images and geologic information about how cool some of these landforms are.
There are many, many more landforms in North and South America and thousands more across the globe. Some of the general landforms that we will discuss in this chapter are mountains, plains, and plateaus.
Plains are large fairly flat areas. You can find them near oceans and we call these coastal plains. Many times coastal plains are referred to as lowlands. Plains contain low rolling hills, swamps, and marshes. Marshes are grassy wetlands, that are usually flooded with water. Lowlands usually have an elevation of zero or below. Elevation is the distance above or below sea level. There are two major coastal plains in the US, the Gulf Coastal Plain and the Atlantic Coastal Plain.
Other types of plains found in the center of land masses are called interior plains. These too, contain low rolling hills and are many times filled with tall grasses and shrubs. In the USA we have an interior plain called The Great Plains. The Great Plains make up the central US. The Great Lakes, Central Lowland, Missouri and Mississippi Rivers are all part of the Great Plains. The great plains once consisted of shallow seas that have been filled in with sediment from the erosion of the Rocky Mountains.
Plateaus are another type of landform. These are large relatively flat lands that have been raised above the surrounding area. Plateaus are made of mostly horizontal rock layers. There are three awesome plateaus in the US: The Colorado Plateau, The Ozark Plateau, and the Appalachian Plateau.
Mountains are landforms that rise high above the ocean and make up some of the most prettiest places on Earth. The highest peak in the US is Mt. McKinley, which is found in Alaska. Mt. Everest found in the Himalayan Mountains is the tallest mountain in the world and rises 8,800 meters above sea level.
There are four types of mountains: Folded, Upwarped, Fault-Block, and Volcanic.
Folded mountains occur when rock layers are squeezed and begin to buckle and fold. The Appalachian Mountains are great examples of folded mountains. They folded about 300 to 250 million years ago. These are also the oldest mountains found in the USA. Once upon a time the Appalachian Mountains were much higher than the Rocky Mountains, but the Appalachians are no longer being built, weathering and erosion are slowly breaking the mountains down. They are now only 2000 or so meters high. The tops of the folds are called anticlines and the bottom of the folds are called synclines.
Upwarped mountains are created when the crust is pushed up by forces within the Earth. Over time sedimentary rock erodes leaving behind the igneous and metamorphic rock. These igneous and metamorphic rocks weather at different rates causing sharp peaks and ridges. Adirondack Mountains in New York are good examples of upwarped mountains.
Fault-Block Mountains are made from huge tilted blocks of rock that are separated from the surrounding rock by faults. On large block of rock tilts up and the other block slides down. A fault is nothing more than a large crack in rock where you can see some movement on either side of the rocks crack. Excellent examples of fault-block mountains are the Grand Tetons and the Sierra Nevadas.
Volcanic mountains form when molten material reaches the surface through weak areas in the crust. As the volcano erupts, material piles up, layer after layer until a cone is visible. Mt. St. Helens and Arenal in Costa Rica are examples of volcanic mountains. Volcanic mountains can appear, grown and shrink in a relatively small amount of time compared to other mountains.
If you want to see visuals some of the mountain types and their formations, watch the following video.
The assignment below is going to have you search for other examples of these types of landforms.
- One person in each group is going to create a Google Doc and title it "Landforms." Then he/she will share it out with the rest of the group and the teacher.
- Create the following table.
Landform Type 2 Examples and Location Origin/Formation 1 image Coastal Plain Interior Plain Folded Mountain Upwarped Mountain Fault-block Mountain Volcanic Mountain Plateau
- In the Examples and Location column, write the name of the landform and in which country it is found. If you use a landform in the USA, make sure you name the state as well.
- In the Origin/Formation column, give a little bit of the geologic history of the area.
- In the Image column, you just need to find one image that is a good representation of the landform.
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