Presentation on theme: "Volcanoes: eruptive style and associated landforms"— Presentation transcript:
1Volcanoes: eruptive style and associated landforms
2Viscosity Resistance to flow Which test tube contains the fluid with high viscosity? Left? Right?
3ViscosityWhich eruption was produced by high viscosity lava? What are the clues?Eruption AEruption B
4Why does one type of lava have a higher viscosity than the other?
5Why does one type of lava have a higher viscosity than the other? Tectonic settingSource of lavaCompositionBasalt: asthenosphere and oceanic crustAndesite: sediments, water, oceanic crust and continental crustLower percentages of silicon and oxygenIntermediate composition