Ch 6 Rapid Changes on Earth Flashcards
creep
slow movement along a fault
earthquake
a sudden movement of part of the Earth’s crust
epicenter
where an earthquake is felt most strongly
fault
crack in Earth’s crust
focus
the point underground where an earthquake starts
landslide
sudden movement of loose rock and soil down a steep slope
lava
molten rock that reaches Earth’s surface
magma
molten rock beneath Earth’s surface
seismology
the study of earthquakes
tsunami
a very large ocean wave
volcano
an opening in the Earth’s crust through which hot ash, gases and molten rock escape from deep within Earth
volcano
an opening in the Earth’s crust through which hot ash, gases and molten rock escape from deep within Earth
Describe two kinds of movement that occur along faults.
- earthquake
2. creep
Describe two kinds of movement that occur along faults.
- earthquake
2. creep
What effect can a violent earthquake have on Earth’s surface?
Earthquakes can move rock and produce new landforms. Over time, mountains can be pushed up and valleys can be formed.
How is the focus of an earthquake different from the epicenter?
The intensity of an earthquake is felt most strongly at the epicenter, which is directly above the focus.
What causes magma to push its way through faults and flow onto the Earth’s surface?
Pressure beneath the surface causes some magma to push its way through faults and flow onto Earth’s surface
as lava
What changes occurred to Earth as a result of the eruption of Mount St. Helens?
The surrounding landscape was completely changed.
Compare and contrast two causes of landslides.
One type is caused by heavy rain, or the sudden melting of snow. Earthquakes and volcanic eruptions trigger landslides. Wildfires can lead to landslides.
What are two ways that rockslides and landslides are alike?
Rock material fall down a hillside in both cases.
