Effects of mineral crystallization on trace elements in melt

[chengkaide]

Hello, everyone， If I study the topic “Effects of mineral crystallization on trace elements in the melt,”，Can I use alphaMELTS2 to simulate the result. If so, how can I start learning the software and finish the task? The rocks are highly differentiated granite.

Thank you ;)

[asimow]

alphaMELTS2 does not yet include trace elements. It will soon. You could compute trace elements in alphaMELTS 1.9, but it does not include the rhyoliteMELTS calibration, which is important for highly differentiated granites. So it is best to wait for the trace elements function to be enabled in alphaMELTS 2. In the meantime, you can use alphaMELTS 2 to simulate the differentiation of your suite to match major elements and obtain mineral modes fractionated at each step. Then you can use that information to post-process the trace element evolution by applying suitable mineral/melt partition coefficients of your choice.

However, there is a very important additional consideration: the trace element evolution of highly differentiated granites is DOMINATED by accessory phases like zircon, monazite, xenotime, etc. but MELTS does not know about these phases. So you may have to modify your calculation by using calibrated equations for the saturation of these accessory phases ... the parameters that you need (P, T, liquid composition) for input to these saturation models are available from the alphaMELTS output.

[asimow]

Also, for learning the software, let me recommend you work through the workshop files and examples from some of our recent workshops, posted on magmasource at https://magmasource.caltech.edu/workshops/caltech/links.php

[Paula]

For anyone else starting out, more up to date set of links is here: https://magmasource.caltech.edu/workshops/goldschmidt/links.php