Types of Mountains - Rutherford County Schools：山-卢瑟福县学校类型.ppt

Types of Mountains 5th Grade TYPES OF MOUNTAINS Volcanic: Folded: Dome: Fault-Block With a partner, predict how each mountain is formed. TYPES OF MOUNTAINS Volcanic: Shield and composite; magma rises from asthenosphere and breaks through the surface of Earth Fault-block: normal faulting and tension Folded: reverse faults and compression Dome: Magma rises through the mantle but does not break through the surface. Fold Mountains Fold mountains are the most common type of mountain. The world’s largest mountain ranges are fold mountains. These ranges were formed over millions of years. Fold mountains are formed when two plates collide head on, and their edges crumbled, much the same way as a piece of paper folds when pushed together. The upward folds are known as anticlines, and the downward folds are synclines. Examples of fold mountains include: Himalayan Mountains in Asia the Alps in Europe the Andes in South America the Rockies in North America the Urals in Russia The Himalayan Mountains were formed when India crashed into Asia and pushed up the tallest mountain range on the continents. In South America, the Andes Mountains were formed by the collision of the South American continental plate and the oceanicPacific plate. Fault-Block These mountains form when faults or cracks in the earths crust force some materials or blocks of rock up and others down. Instead of the earth folding over, the earths crust fractures (pulls apart). It breaks up into blocks or chunks. Sometimes these blocks of rock move up and down, as they move apart and blocks of rock end up being stacked on one another. Often fault-block mountains have a steep front side and a sloping back side. Fault-Block Examples of fault-block mountains include: The Sierra Nevada mountains in North America The Harz Mountains in Germany Dome Dome mountains are the result of a great amount of melted rock (magma) pushing its way up under the earth crust. Without actually erupting onto the sur