The Moon: a Geologist’s Tale (by sarah)
Ok I wont bore you with everything but basically I can not express how much I enjoyed yesturday, all the stress was worth it and then some. I went to the office to try and sort out what was happening and apparently Registary removed me from the list when they should not have and it is being chased. Its a good job I checked (which I only did becuase of Carina as I was being nervous and shy and scared of a giant inflatable yellow pig!) it turned out that my lecture was at six and not seven so I almost turned up an hour late!
I windled away the time looking around the geohazards offices with Carina - she's doing a PhD at UCL in volcano early warning systems (basically she's doing a cross over between social science and geology which should actually be quiet useful). You can find out about her project etc... here. I spoke to some of her collegues and got recognised as the wrong person and informed that I had meet a supervior before and was working with someone I'd never heard off - this is what I get for walking around an office for PhD students looking at home. Of course mistaken identity though he recalled my name which was impressive as Carina only mentioned it in passing!
Chatting to others in her office I found that one off them was ex-Birkbeck and the other informed me that the igneous petrologist might indeed now be interested in my project as she has become obsessed with meteoritics - this is useful info.
After double checking everything I was almost late as I was drinking tea and reading my book when Carina suddenly announced that it was quarter to six - eek! And I didn't didn't know my way out of her building!
But as it happened I passed Ian Crawford (the lecture) going the wrong way. He hastily said he'd be back and scuttled off. I found the room having picked up a scared undergraduate on rout who was looking for vertabrate paleo. The first thing that struck me was that there were a lot of women in the room - over half - this contrasts to last time. I felt a pang of sadness that it wasn't the people I'd got to know last time but then I knew that would be the case as even those who resat did that two years ago. I suddenly thought - woaw I've not done geology for about three and a half years - eek.
I sat down everyone was silent.
I managed to have to loudly rummage for my pen and paper.
Then Ian arrived and we delved into the world of lunar geology. To my suprise I guest correctly why the crater near the south pole on the farside is not nicely circular like the other mare (or seas - they are the dark patches you see). i probably didn't use the right terms but I said it had been erroded by other impactors. Yay! I was right but a bit later I stared at the photos of thin section and could not recall the name of the minerals and lunar minerallogy is simple - really really simple. I was staring a Ca-rich plagioclase and pyroxenes and ilmentite. We even had them in cross polars - mew 🙁 And as for the spherals of orange olivine glass at least I remembered that an amorphous glass would come out black under cross polars (cross polars are like a filter on light transmitting microscopes).
We did a bit on lunar stratigraphy where I actually interupted the class to ask a question - for those of you who know me well you'll know I don't do such things lightly as I get shy not to mention the class was over running from what he had origonally said. I asked if the graph was assuming a constant rate of impacts as the number of impact creators is used to date bits of the moons surface - this is obviously relative dating rather than absolute but I was sure that there would have been more impacts early on when there would have been more debris and therefore that would need to be accounted for. I was pretty sure I had even seen somewhere in the distanct past something to do with a high early impact rate.
I got a , 'good question.' Which I always consider a good thing to have said. He did however then point out that there where points on the graph showing the bore hole data brought back from the Apollo missions. In other words the graph was constrained by those data points which where radiometricaly dated (they had used isotopes and was therefore about as absolute as dating gets). This ment the graph was indeed showing that the impact rate had not been continious - I thought doh! I should have seen that! However he did point out that the number of data points was pathetically small.
This is also the data they use to date all the other bodies in the solar system but as far as I could tell its all guestamets and is very very relative. Like assume more impacts on mars per time unit becuase its bigger - I mean how do you actually scale something like that? Also I would have thought that proximaty to say an asteroid belt and/or large bodies such as a gas giant would affect the rate of impact on a planetary surface.
I found myself hooked - I want to find out more. So much so that I spent the train journey home (which was itself very eventful) reading the papers I'd got about isotopic abundence in the moon. Even once I got home which was gone 1 o'clock I couldn't stop and carried on reading.
My main issue with the day was that two train journeys, sitting down for most of the afternoon and then having two slightly longer than an hour lectures acted up my back and pelvis - the pelvis actually started clicking before I got back to Padington and I felt the familiar 'toothache' in my hip and knee. Fortunatly I had come prepared and quaffed a pain killer - I aslo had my special jel with me etc...
The only trouble is that today I felt a restless depression becuase I want to be geologising and not tidying my house. Still more goelogy tomorrow 🙂
Tue 30th Sep 2008 8:02 pm 
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By Clare, Wed 1st Oct 2008 @ 12:32 pm
So glad you enjoyed it me dear. You know when I move into my flat you are welcome to stay any time. xx
By Becca, Wed 1st Oct 2008 @ 5:14 pm
It's awesome that you're back doing geology again! Hope you enjoy it! Becxx