Volcanoes - AQAMonitoring volcanoes - popular techniques
Composite and shield volcanoes are found along plate margins. They have distinctive characteristics and can have both positive and negative effects on people and the landscape.
Volcanic eruptions are unpredictable. However, scientists can monitor volcanoes to estimate when they are likely to erupt. Scientists can use a variety of techniques to do this, such as:
seismometerA machine that detects seismic waves caused by earthquakes. - used to measure earthquakes occurring near an eruption
tiltmeterA device that measures any changes in the 'tilt' of the landscape. It is used often for studying volcanoes. and GPS satellites 鈥 these devices monitor any changes in landscape. Volcanoes tend to swell near an eruption
monitoring gases escaping from a volcano using robots called Spiders 鈥 often there is an increased release of sulphur dioxide near an eruption
measuring temperature - volcanoes become hotter when magma starts to rise through the main ventThe thin narrow pipe in the middle of a volcano that connects the magma chamber to the crater.
looking at the past history of eruptions - scientists can identify patterns of activity