Volcano - 5th grade


Terms in this set (...)

a mountain that builds up around an opening in Earth's crust
volcanoes will force materials from Earth's
interior out of its opening
molten rock in the earth's crust
all form of melted rocks that reach the Earth's surface
opening in a volcano
a bowl-shaped opening at the top of a volcano
the hole that forms when a volcano collapse inside itself
active volcano
a currently erupting or recently erupted volcano
dormant volcano
volcano that does not erupt for some time
extinct volcano
volcano that stop erupting
harden magma in vertical or nearly vertical cracks
harden magma between horizontal layers of rock
magma pushed upward to form a dome shape
a huge and irregularly shaped underground magma formations
shield volcanoes
built by thinner, fluid lava that spreads over a large area and has a broad base and gently sloping sides
cinder-cone volcanoes
built by thick lava that is thrown high into the air and falls as chunks or cinders and form as a cone shape
composite volcanoes
Formed when alternating layers of ash, cinder and bombs build up.
where volcano form?
- Form where Earth's plates move apart.
- The space between the moving plates allows magma to rise to the surface
Types of active Volcanos:
a. Shield volcanoes
b. Cinder-cone volcanoes
c. Composite volcanoes
What causes earthquakes?
1. Caused by sudden movement along a fault
2. When forces push and pull a plate, energy builds up
3. Then energy is released
the place where the slipping begins
How Earthquakes travel?
1. Begin below the ground
2. Vibrations ( waves) move through Earth in all directions
Measuring seismic waves
Seismograph detects and records earthquakes
Measuring earthquake's energy
1. Magnitude
2. Richter scale
3. After shock
is the measure of the amount energy released by an earthquake
Richter scale
measure magnitude
1. it rates earthquakes from weakest to strongest
are earthquakes with lesser magnitudes. They usually felt after the main earthquake
Different types of waves
1. Primary waves
2. Secondary waves
3. Surface waves
Primary waves
1. move the fastest
2. they pass through both the solid and liquid layers of Earth
3 move back and forth as rock squeezes and spreads
Secondary waves
1. half as fast as primary
2. move through only the solid layers
3. move up and down
Surface wave
1. travel along Earth's surface.
2. cause the most damage
Earthquake Safety
a. During a major eathquake, buildings and roads may break apart
b. Bridges might collapse
c. Indoor safety
- Keep away from windows and walls
- Duck under a table or doorway
d. Outdoor safety
- stay away from trees, power lines, and anything that might fall down
Earthquakes in the Ocean
a. Some earthquakes strike below the ocean
How do scientist study earthquakes?
Seismic waves - the vibrations caused by earthquakes