Volcanoes Chapter 6 Lesson 2

Molten rock that reaches Earth's surface.
The molten rock beneath Earth's surface.
An opening in Earth's crust through which hot ash,gasses and molten rock escape from deep within the Earth.
What caused magma to push it's way through faults and flow onto Earth's surface?
Pressure builds up in the center of Earth which then Magma makes its way through faults and pushes its way out, turns into lava.
How might volcanoes be dangerous?
Hot lava is fast moving and ashes flying through the air can hurt you.
How will tte landscape around a volcano change if lava flows over it?
a) All the trees and vegetation disappear and burn up.
b)Lava cools and creates new rock and surfaces.
What is the difference betwwen lava and magma?
Magma is molten rock beneath the surface.Lava is above the surface.
Where did the material that was the north side of Mount St. Helens go?
It was dispersed all over the landscape.
What parts of the volcanic eruption would have destroyed the forest around Mount St. Helens?
d)Water (from melted ice)
e)Materials from the explosion.
What changes occurred to Earth as a result of the eruptions of Mount St. Helens?
Rock,soil, mud and water slid down the mountain side. The north side was destroyed.
How does a volcano change Earth's surface?
Hot ash, gases and molten rock pour out and destroy everything it touches and adding new rock where there was nothing before.
Refer to the diagram to explain how a volcano erupts?
1)Inside a volcano, pressure builds.The pressure pushes MAGMA upward.
2)Magma pushes toward Earth's SURFACE through CRACKS.
3)Hot LAVA, gases, and ROCK flow from the volcano.
4)Lava COOLS, hardens, and becomes part of the LAND.
Earthquakes and volcanoes often occur in the same areas. Why might this be?
Earthquakes occur near faults . Faults are also what molten rock need to get to the surface.
A volcano erupts when pressure pushes molten rock up through cracks in Earth's crust onto the surface.Volcanoes change Earth's surface. Describe two ways that volcanoes erupt?
a)Molten rock pushes up through cracks in Earth's crust.
b)An explosion of ash, lava and magma. This changes Earth's surface.
What changes occurred to Earth as a result of the reuption of Mount St. Helens?
1) Trees and forest were destroyed and gone.
2)One side of the mountain was blown away.This left a huge crater, or hole in the earth.
3)Ash from the eruption reached 11 other states.