So I went round my parents house at the weekend, for a quick catch-up since my France trip, and ended up revising my continental geology textbook in the garden whilst my little sister drew on a whiteboard.
She drew a volcano, a pretty generic strato-type cone, and proudly announced to me that she knows how to draw them now because she watched Aloha Scooby Doo the other day.
Uh-oh. Once my brain’s in geo-mode I can’t seem to stop. Aloha = Hawaiian, and I know there are no stratovolcanoes on Hawaii.
So I said to her, ‘Well, Scooby Doo’s wrong.’
Cue blank stare.
‘Shall I tell you why?’
‘Okay,’ she agrees enthusiastically.
So I tell her that Hawaii is full of shield volcanoes, which look very different to the sticky lava cone she has just drawn. I draw her an example on the whiteboard, and I show her what pahoehoe lava looks like, and she says ‘Coool.’ When she found out that sometimes the lava in Hawaii can flow so slowly you can outwalk it, she drew a couple of guys walking past my pahoehoe flow with a wee speech bubble saying ‘Catch up!’
I them draw some lava bombs coming from the top of her stratovolcano, and tell her this is a Strombolian type eruption, and that I went to Stromboli last year. I told her I’d watched the eruptions from the side of the volcano itself, but that it was safe because the eruptive material always tended to go down the same ash slope, so we could avoid it. She proceeded to draw a little stick figure me halfway up the volcano.
Then I showed her another type of volcanic eruption, Plinian eruptions. I drew a picture of a lava dome resembling Mt St Helens for ease of understanding, and explained that in these kind of eruptions, there are huge clouds of ash that kill more people than the lava does. I told her about Pompeii – she’s pretty young still, and hasn’t yet done the Romans at school – and when it got to the fossilised ash people thing, she was pretty horrified. To annotate my diagram she drew a person lying on the ground to signify one of the ash mummies and added a ‘x1000’ after it.
She was still pretty hungry for more info, so I told her about hydrothermal vents, to which she replied, ‘Oh I saw something about those on TV.’ I told her that the crabs and worms that live there feed off the chemicals from the vents, and can live on the sides of the vents even though it’s very hot.
She then told me a fact – that islands are actually mountains rising up from the sea floor. She even drew me a picture of it. I said ‘Did you know you can get mountains under the sea too?’ and she was astounded. We added an undersea mountain chain to our diagram.
I didn’t do much revision after that, teaching was too much fun.
Later we watched Futurama, in which they happened to go up Olympus Mons. I realised they’d made the mistake of drawing it as a stratovolcano, exactly the same as Scooby Doo had done, but I think by now I’d given my sister enough food for thought. Maybe I’ll tackle Olympus Mons next time!