Objectives • Classify mountains according to how they are formed. • Describe the Himalaya Mountains. • Explore the relationship between plate tectonics and mountain formation.
The Himalayas • The Himalayas are the tallest mountains in the world. • They are located on the border of China and India. CH-152.0
What do you think? • How were the Himalayas formed? • Why are the Himalayas the tallest mountains in the world? CH-153.0
Investigating the Question • Mountain ranges are formed by plates made from the earth’s crust that move against each other. • The plates that form the Himalayas are still moving! • How do you think this affects the mountains today?
Plate Tectonics Eurasian Plate • The earth’s crust is split into several plates. • These plates float on top of magma (a hot, thick, gel-like substance). Plates Indian Plate CH-155.0
Plate Tectonics Eurasian Plate • When currents inside the earth move the magma, the plates move, too. • This movement sometimes causes mountains to form. Plates Indian Plate CH-155.0
Just Checking Answer the following questions on your worksheet • The earth’s crust is split into __________. • The hot, thick, gel-like substance found within the earth is called ___________. CH-156.0
There are 3 types of mountains: • 1. Volcanic Mountains • 2. Fault-block Mountains • 3. Folded Mountains CH-157.0
Volcanic Mountains • Volcanoes form when magma within the earth pushes its way up through the crust. • While pushing through the crust, the pressure causes the surrounding crust to rise, forming a mountain. • Magma is deposited on the surface, sometimes creating a cone shaped mountain. CH-158.0
Fault Fault-block Mountains • Fault-block mountains form when rock layers break and form a fault line. • As the two blocks are being pushed together, the pressure forces one block up and the other block down. • The block that is forced upward forms a mountain. CH-160.0
Folded Mountains • Folded mountains form as two plates move toward each other. • The plates push against each other causing the crust to fold or ripple • This is like when you push 2 ends of a piece of paper together and the middle bends or folds. CH-161.0
Just Checking Fill in the blanks on your worksheet • Mountains that form when magma within the earth pushes its way up through the crust. __________ • Mountains that form when a plate cracks and forms a fault line. ______________ • Mountains that form when plates push up against each other causing the crust to fold or ripple. ______________ CH-162.0
Denser plate Himalayas • The Himalayas formed as a result of the Indian Plate and the Eurasian Plate moving toward one another. • When two plates collide, they will do one of the following: 1. If one plate is denser (heavier) than the other, it will sink below the other plate 2. If both plates have the same density, they will continue to push against one another resulting in folded mountains. Same Density CH-163.0
The Himalayas • Both of these plates are the same density. • As the plates keep pushing against each other, there is no place for the crust to go except to bend upwards. • The plates are still running into each other and the Himalayas are growing by more than 1 cm each year. Himalayas Indian Plate Eurasian Plate CH-164.0
Just Checking Answer the following questions on your worksheet • The Himalayas are ___________ mountains. • The Himalayas are the result of what two plates running into each other? • ________________ and _______________ • Neither of these two plates is sinking because they are both the same ___________. • The Himalayas are still growing at a rate of ___________ each year. CH-165.0