5.3.3

Question 1

Outline the regularity of volcanic eruptions of shield volcanoes and stratovolcanoes

Answer 1

Shield volcanoes tend to be found at constructive plate margins and are typified by high frequency, low magnitude eruptions
Stratovolcanoes tend to be found at destructive plate margins and are typified by low frequency, high magnitude eruptions

Question 2

Explain how volcanic events are predicted

Answer 2

Volcanologists (scientists who study volcanoes) monitor changes using GPS, tilt meters, satellites, seismometers and gas detection
Signs of an eruption include:
Magma rising which can be detected by heat sensors and satellites
Ground deformation as rising magma causes bulges
Increased emissions of sulphur dioxide and other gases
Increased seismic activity caused by magma movement detected by seismometers