Going over Volcanic Hazards notes. Heard of Mt Pelee?
No?
Ok, well the above is a picture of it’s 1902 eruption. It’s situated in the West Indies, and forms part of the island Martinique. During the main eruption the ash column collapsed and swept through the city of Saint Pierre, killing almost all of it’s approximately 30,000 citizens and various refugees. (The refugees were as a result of the initial destruction caused by the preludes to the main eruption - lava flows, ash fall, etc.)
Only a handful survived, most dying later on due to burns. The main notable survivor was a prisoner, Ludger Sylbaris who had been thrown in for assault (some sources say murder apparantly) the previous night. The only reason he survived was because he was in a partially underground cell with no windows. The cell can still be seen today actually.
I somehow find it slightly funny that of all people to survive it was a man who was breaking the law.
I Wrote A Poem, Which I Almost Never Do
Liked it, though. It’s science-y
Love and Lava
My love, like a volcano, spurns
And puzzles the scholastic
My desire like the crater burns
My passion, pyroclastic.
Your woes, like frightened farmers, flee
From numerous ejections
Which bury villas by the sea
In layers of affections
I'm such a geek.
I just got really overexcited about how I totally understood what I was reading when I looked up this: http://en.wikipedia.org/wiki/Schwarzschild_radius
Effectively, it’s the theory and equation that first proposed the concept of a black hole and a supermassive black hole. All I could think was ‘How awesome is this?!’ Honestly, I don’t know what to do about my overenthusiastic geekiness sometimes. That is properly cool though.
Good example: today in my 9 am exam for Volcanic Hazards, I had a BRILLIANT time for my first two questions, because I was talking about stuff that I genuinely find fascinating and really cool. Ditto my one good essay question for my Wednesday Human Palaeoecology exam on Homo sapiens diets and how meat effected our brain size in evolutionary terms. My questions today involved talking about the chemical composition of magma and how it effects the lava flows characteristics, followed by a question on the classification of volcanic hazards. (To be honest I just waffled on about each hazard - I don’t think that’s really what they’re looking for… oh well. I wrote four pages on it.)
The chemical composition things is really cool though. If a magma has a high level of silica, it’ll be very viscous with a low temperature (less than eight hundred degrees celsius) and will result in acidic rocks (like rhyolite). It’ll lead to Plinian eruptions and stratovolcanoes - so basically the most explosive and dangerous eruption you can get without it becoming phreatomagmatic (water getting involved makes things a hundred times more explosive). The lower the silica content and the higher the Magnesium content, the less viscous the magma - resulting in Hawaii style fissure eruptions (effectively holes in the ground) and very little danger to the populace. Aside from ending up with lava in your front room instead of a wall, but then that’s your own fault for building your home in a lava field in Hawaii. Moral of the story kids: Always check the local geology out before you definitely move in. It saves lives.
OH MY GOD I’M SUCH A NERD. I’m going to shut up now.
