Fold mountains are the most common and most massive types of mountains on Earth, at least. In order to understand how fold mountains form and develop, we have to think about plate tectonics. There are seven major tectonic plates and several smaller ones all across the world. When two plates collide, several things can happen.
For instance, if one plate is denser than the other oceanic plates are typically denser because of the type of rocks that make up the plate , a process called subduction will start: the heavier one will slowly glide beneath the lighter one. If they have relatively similar densities, then they will start to crumple up, driving movement upwards. Essentially, the tectonic plates are pushed, and since neither can slide beneath the other, they build up geological folds.
To get a better idea of what this looks like, try to push two pieces of papers towards each other: some parts will rise up, representing the process of mountain formation. This process is called orogeny giving birth to mountains and it generally takes millions of years for it to complete.
While the previous category was all about folds, this one is all about faults: geological faults, that is. As the pressure grows and grows, at one point the rock will simply break. Their size can vary tremendously, from a few centimeters to mountain-sized. Basically, when big blocks of rock are broken through faulting, some of them can get pushed up or down, thus resulting in block mountains. Higher blocks are called horsts and troughs are called grabens.
Still, the Sierra Nevada mountains an example of block mountains , feature a block km long and 80 km wide. Another good example is the Rhine Valley and the Vosges mountain in Europe. Rift valleys can also generate block mountains, as is the case in the Eastern African Rift. It can be quite difficult to identify a block mountain without knowing its underlying geology but generally, they tend to have a steep side and a slowly sloping side.
Volcanic mountains are created when magma deep beneath the surface starts to rise up. Report Error Is there an error in this question or solution? Chapter 2: Endogenetic Movements - Exercise [Page 20]. Share 0. Select a course. My Profile. My Profile [view full profile]. Inform you about time table of exam. Inform you about new question papers. New video tutorials information. Domes that have been worn away in places form many separate peaks called Dome Mountains.
Volcanic Mountains. As the name suggests, volcanic mountains are formed by volcanoes. Volcanic Mountains are formed when molten rock magma deep within the earth, erupts, and piles upon the surface. Magna is called lava when it breaks through the earth's crust. When the ash and lava cools, it builds a cone of rock. Rock and lava pile up, layer on top of layer. Plateau Mountains Erosion Mountains.
Plateau mountains are not formed by internal activity. Instead, these mountains are formed by erosion. Plateaus are large flat areas that have been pushed above sea level by forces within the Earth, or have been formed by layers of lava.
Plateau mountains are often found near folded mountains. As years pass, streams and rivers erode valleys through the plateau, leaving mountains standing between the valleys. Follow me on Twitter mbarrow. This site uses cookies. See our Cookie Policy for information. You may not redistribute, sell or place the content of this page on any other website or blog without written permission from the author Mandy Barrow.
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