The Year 4 Classes all agreed that today’s lesson from visiting volcanologist, Dr James Hickey, was their best lesson ever!
Dr James Hickey, Senior Lecturer in Geophysics and Volcanology at the University of Exeter, had the children thrilled and enraptured as he talked to them about his studies of volcanoes.
The children learnt that as the magma rises up the conduit, tiny bubbles in the magma grow bigger and multiply. These bubbles eventually turn into a stream of gas with bits of magma stuck into it. The magma literally gets blown apart by the pressure of these bubbles.
The children then found out that there were two types of eruption; effusive and explosive. Effusive eruptions occur with runnier magma and typically form shield volcanoes. Explosive eruptions involve stickier magma and form stratovolcanoes with steeper slopes of lava and ash.
The high point of the lesson was undoubtedly the volcano experiment. Using coke bottles as the magma and conduit, Dr Hickey added mentos to create bubbles and simulate an eruption.
The children found that the more bubbles created, the bigger the explosion and the larger the displacement of magma (or cola). By changing the size of the vent (or the cap of the bottle), they could increase the pressure and make the explosion stronger. It was fabulous to see the joy on their children’s faces as the reactions occurred.
A huge thanks to Dr Hickey for taking the time to visit us today and for creating such an exciting lesson for us all.