Volcanoes

Today we did a bit of touring of the Hamilton area, which is famous for being a volcanic area. Unfortunately the volcanic discovery centre nearby wasn’t open (being a public holiday), but we still saw some cool stuff. We first went to the Byaduk caves, which formed 32,000 years ago when the Mt Napier volcano last erupted. It was a composite volcano, and apparently it started as lava flowing out the top quite slowly (walking pace) which went on for about a month, and then at the end there was a violent explosion and a huge amount of volcanic rock flew hundreds of metres into the air, which from memory is called Scoria. We saw lots of examples of it lying around on the ground which has a lot of little holes in it (air pockets) and was reddish. It’s also quite light because of the air pockets. There were four caves there, one of which you could climb into. Apparently there are bats in there but we didn’t see any – lots of ferns and moss though. The caves were all formed when Mt Napier erupted and lava flowed through valleys forming lava tubes. The outside of the tubes cooled and hardened while the lava inside kept flowing, and then the roof of some parts caved in, creating the caves. After that we went to see some Tumuli, or lava blisters, nearby, which are these really cool mounds of volcanic rock. There’s between 20 – 30 of them in someone’s private field, and it looks like someone just came along and created these huge piles of rocks, some of them the height of a house. They’re the best ones in Australia apparently, and they were created when pressure from the lava underneath the earth became so great that they caused little eruptions and the rocks burst out (at least, I think I’m remembering it right). I’ll try and download the photo too so that it makes more sense.

After the Tumuli we had a nice sandwich lunch at Mt Eccles near Lake Surprise, but didn’t do the walk in the end, just came home to catch the second half of the Essendon – Collingwood game which is going exactly the way Michael and Kathy would like it to (so far).