The Restless Earth Flashcards
Composite volcano
A composite volcano gets bigger and bigger the more it erupts. The ash and the lava from each eruptions forms layers. These layers make new rock which makes the volcano bigger and bigger.
Lava
Boiling hot (molten) rock that has erupted out of a volcano (and is therefore above ground), that will harden to become rock again in time.
Crater
The dent in the top of a volcano caused by the blast of the eruption.
Magma chamber
Place below ground were the molten rock sits and boils, waiting to erupt
Magma
Boiling (molten) rock from the earth’s core sitting below ground and waiting to erupt.
Shield volcano
A volcano that builds up from countless outflows of runny lava.
Cinder cone volcano
A volcano that is built from blobs of lava that are ejected from a single vent.
Composite volcano
Volcanoes that are made up of layers of ash, lava and volcanic debris.
What are earthquakes?
A vibration of the earth’s crust caused by sudden release of stored energy in the rocks found along fault lines
When do earthquakes occur and how?
They occur when there is plate movement along plate boundaries.
When the rocks can no longer withstand the increasing stress they can suddenly slip many metres, causing an earthquake
Magnitude
The amount of energy released during an earthquake
Richter scale
Used to measure the magnitude of the earthquake
Each increasing magnitude on the richter scale is 10 times greater in magnitude than the previous one.
strongest earthquake is 9.5 on the richter scale in valdivia child
Seismograph
Used to measure where earthquakes are.
Can find the epicentre
Epicentre
The point on the earth’s surface vertically above the focus of an earthquake.
Tsunamis
A series of large waves generated by an abrupt movement on the ocean floor that can result from an earthquake, an underwater landslide or a volcanic eruption.
