The purpose of this lesson is help your students thoroughly understand the 3 types of mountains- folded mountains, fault-block mountains, and volcanic mountains- plus how and why each set of mountains form. Though this is a lot of information, the student handout consists of a table with rows and columns that they’ll fill in for folded mountains, fault-block mountains, and volcanic mountains throughout the lesson. Seeing the information that way will make it much easier for them to understand and remember all this information.
Since all mountains are the result of a hot core, the lesson begins deep within the earth by explaining how this is so. On their handouts, students will copy 3 key statements from the PowerPoint the explain that the core is hot, which in turn causes magma in the mantle to spin, which then causes the plates floating on the magma to move. And hence folded mountains, fault-block mountains, and volcanic mountains!
With the main cause of all this set in place (earth’s hot core) we’ll start filling in the lower portion of the handout. It’s designed with 3 sets of columns that compare the cause of the mountain type, kind of stress, result of that stress, and examples. The columns will be filled with information about the 3 types of mountains- folded mountains, fault-block mountains, and volcanic mountains.
In the first column (folded mountains) we’ll begin with a drawing of folded mountains, which result from the hanging wall and footwall being squeezed. To illustrate this, the PowerPoint will show a huge simple-to-draw example of folded mountains, complete with a labeled footwall and hanging wall that students will draw on their handout. The drawing will also include arrows pointing towards each other, showing how the hanging wall and footwall are squeezed, causing the hanging wall to rise and the footwall to lower, which we call folded mountains. Below that drawing is a space to list the cause of the hanging wall and footwall being squeezed; in this case it’s a reverse fault. Then we’ll discuss and write down what type of stress is responsible for the hanging wall rising and footwall lowering; in this case it’s compression. Next we’ll record the result, which is the rock in the hanging wall goes up, which resembles a fold (hence the name ‘folded mountains’). Lastly, we’ll give 3 examples of folded mountains on earth (Appalachians, Himalayans, Alps).
The second column is where we’ll go through all of those same features for fault-block mountains. Like last time, we’ll begin with a drawing of the fault-block mountains, which result from the hanging wall and footwall being pulled apart, and that in turn causes the footwall to raise and the hanging wall lowers. Below the drawing of fault-block mountains, the cause of all this is because it’s a normal fault, where forces pull either sides of the fault apart from each other. After that, we’ll state the kind of stress causing this- tension. Then we’ll record the result, which is the rock in the footwall goes up and the hanging wall down. Lastly, we’ll give 3 examples of folded mountains on earth (Tetons, Sierra Nevadas, Harz).
In the third and last column we’ll go through all of those same features for volcanic mountains. The drawing will feature a classic-looking volcanic mountain with a magma chamber below the crust, erupting violently. The cause of volcanic mountains will be listed as convergent boundaries, and stress will refer to the fact that at convergent boundaries compression squeezes rock together. The result is that is that pressure causes magma to erupt onto earth’s surface. 3 examples-Mt. St. Helens volcanic mountain, Mt. Hood volcanic mountain, and Mount Fuji volcanic mountain.
Key words: core, magma, convection, crust, tectonic plates, folded mountains, reverse fault, compression, hanging wall, footwall, fault-block mountains, normal fault, tension,volcanic mountain, ash, lava, magma, vent, crater, convergent boundary