Forums · The "CKY should be revising but can't bring himself to start, and doesn't have IRC, but still wants distractions" topic
I think the title sums this up nicely. No IRC for times of boredom like these is pretty sucky. Admitedly, I could just go watch my flatmates get drunk, but that's just depressing when you have an exam the next day. And at least if I'm in my room, I can kid myself that I'm accomplishing something, even if I just end up watching random youtube vids.
Sooooo, what's up people?? I notice that there's suddenly a major upheaval of the analyses, which is cool. The example one looks amazing, if they all end up like that, that'll be very impressive. I'd like to get involved, but exams are really stressing me right now, so that may have to wait...
I could carry on with various ramblings - hell, if revision goes really badly, I might try and write something as huge as a slowflake rant. Unlikely, but who knows the extent I'll go to to avoid revision.
I'm aware that this topic has no point, but I figured I'd say hi. Now, if anyone could explain a eutectic phase diagram to me, that'd be much appreciated...
Sooooo, what's up people?? I notice that there's suddenly a major upheaval of the analyses, which is cool. The example one looks amazing, if they all end up like that, that'll be very impressive. I'd like to get involved, but exams are really stressing me right now, so that may have to wait...
I could carry on with various ramblings - hell, if revision goes really badly, I might try and write something as huge as a slowflake rant. Unlikely, but who knows the extent I'll go to to avoid revision.
I'm aware that this topic has no point, but I figured I'd say hi. Now, if anyone could explain a eutectic phase diagram to me, that'd be much appreciated...
Hi.
Does this help at all?
The binary eutectic phase diagram explains the chemical behavior of two immiscible (unmixable) crystals from a completely miscible (mixable) melt, such as olivine and pyroxene, or pyroxene and Ca plagioclase. Here we are going to generalize to two minerals, A and B, or P and Q. We want to observe the behavior of this system under two conditions, one of complete equilibrium during crystallization when all chemical reactions can run to completion, and the second of disequilibrium when fractionation occurs and igneous rocks evolve.
The conventions for the phase diagram include the following:
Two immiscible components: such as CaAl2Si2O8 (calcic plagioclase) and FeMgSiO4 (olivine) plotted along the horizontal axis, OR olivine (isolated tetrahedra) and pyroxene (single chain tetrahedra). They are immiscible because they have different crystal structures.
One variable, temperature, plotted along the vertical axis. Pressure is held constant at 1 atmosphere.
Three phases, crystal A, crystal B, and melt.
Complete miscibility of the melt (magma)
The assumptions are:
The system remains in equilibrium throughout its history so that all reactions can take place and everything can come to stability.
Everything in the original melt remains in communication throughout the crystallization process.
Edit: Heres a good distraction for you.
http://awesomeyay.com/games.php?act=play&id=340
Does this help at all?
The binary eutectic phase diagram explains the chemical behavior of two immiscible (unmixable) crystals from a completely miscible (mixable) melt, such as olivine and pyroxene, or pyroxene and Ca plagioclase. Here we are going to generalize to two minerals, A and B, or P and Q. We want to observe the behavior of this system under two conditions, one of complete equilibrium during crystallization when all chemical reactions can run to completion, and the second of disequilibrium when fractionation occurs and igneous rocks evolve.
The conventions for the phase diagram include the following:
Two immiscible components: such as CaAl2Si2O8 (calcic plagioclase) and FeMgSiO4 (olivine) plotted along the horizontal axis, OR olivine (isolated tetrahedra) and pyroxene (single chain tetrahedra). They are immiscible because they have different crystal structures.
One variable, temperature, plotted along the vertical axis. Pressure is held constant at 1 atmosphere.
Three phases, crystal A, crystal B, and melt.
Complete miscibility of the melt (magma)
The assumptions are:
The system remains in equilibrium throughout its history so that all reactions can take place and everything can come to stability.
Everything in the original melt remains in communication throughout the crystallization process.
Edit: Heres a good distraction for you.
http://awesomeyay.com/games.php?act=play&id=340