Prac 5
Crystallization sequences
Please return your answers no latter than Wednesday, 22 March
I. Thin sections
Make a large sketch of your thin section (do not forget to mention the number!).
Again, it need to be sufficiently large to capture the texture of the rock and show the
relations between the minerals. Please take care to ensure that your sketch and your
comments are consistent!
Propose a sequence of crystallization for your sample, indicating the order in which
the mineral formed (and why you think so).
II. Interpretation
Using the diagrams and informations from the course, as well as the web/library/etc.
resources, interpret the texture and sequence observed in your rocks. You will
probably need to use concepts such as phase diagrams1, rock composition,
temperature of emplacement, etc.
1
Now, you didn’t really expect to escape this, did you?