page last updated: 28.11.2011

# Tutorials

A range of tutorial exercises are provided:

- Constructing diagrams (PT pseudosections, PT-x, PT-xCO2, mu-mu)
- Isopleths
- Using rbi
- Buffering calculations

Each tutorial is rated according to difficulty and experience in using thermocalc:

- Padawan Learner (welcome, Younglings)
- The tasks are fairly straightforward and/or each step in the calculation is outlined in detail

- The tasks are fairly straightforward and/or each step in the calculation is outlined in detail
- Jedi Knight (use the force, Luke)
- These assume you have already completed the Padawan Learner level tutorials. Less detail and/or somewhat trickier calculations are involved

- Jedi Master (these are not the droids you're looking for)
- These assume you are already adept at using thermocalc but are interested in more complex calculations

- Jedi Grand Master (“Ready are you? What know you of ready?")
- These are more involved calculations that deal with less commonly drawn diagrams

The basic level tutorials are all related (same system and based on the same bulk rock composition). If you are new to thermocalc I recommend you do the tutorials in the following order

- PT-pseudosection tutorial 1
- T-x pseudosection tutorial
- Using a T-x diagram to start a new P-T pseudosection tutorial
- PT-pseudosection tutorial 2
- Mode and composition isopleth tutorial

## Tutorials for Constructing Diagrams

The diagram construction tutorials:

### P-T-pseudosection tutorial 1 (by Richard White)

Rating: Padawan Learner

Updated: 29/03/2010*

This tutorial is a base level instruction for constructing a P-T pseudosection. It starts with the very basics. This tutorial is based around calculating and drawing the NCKFMASH pseudosection Fig. 8b in White, R.W., Powell, R. & Holland T.J.B., 2007. Progress relating to calculation of partial melting equilibria for metapelites. Journal of Metamorphic Geology, 25, 511–527.

As with that figure, I have not bothered to calculate the muscovite-bearing assemblages that would occur in the top left of the diagram. A copy of the finished diagram is included in this tutorial download. This download now contains additional files and instructions for doing the tutorial using thermocalc 3.33*.

In the following description assemblages are given as lists of phases separated by dashes (e.g. cd-bi-sill-pl ) and phases set to zero to calculate lines and points are given in brackets (e.g. (cd) or (cd sill) ).

Before starting this tutorial you should look at the “getting started” section of the webpage and the documentation.

### T-x pseudosection tutorial (by Richard White)

Rating: Padawan Learner

Updated: 29/03/2010*

This is a basic level tutorial on how to construct a T-x diagram. It assumes you have a basic understanding of how to operate thermocalc (from PT-pseudosection tutorial 1). The calculation is in NCKFMASH and the X axis is XAl (Al2O3/(Al2O3 + FeO + MgO)). **This download now contains additional files and instructions for doing the tutorial using thermocalc 3.33.***

### Using a T-x diagram to start a new P-T pseudosection tutorial (by Richard White)

Rating: Jedi Knight

Updated: 29/03/2010*

In this tutorial I will go through the process of building a T-x pseudosection from a known bulk (where the P-T pseudo has already been constructed) to a new composition. This is a useful way to start a new diagram. The known bulk composition is that of White et al 2007 Fig 8b (as constructed in P-T-pseudosection tutorial 1). The new composition is one I just made up (the composition used in P-T-pseudosection tutorial 1). The T-x diagram will be constructed at 5 kbar over a T range of 700-860°C, and some additional calculations at 6.4 kbar.** This download now contains additional files and instructions for doing the tutorial using thermocalc 3.33.***

### P-T-pseudosection tutorial 2 (by Richard White)

Rating: Jedi Knight

Updated:29/03/2010*

This tutorial is a more advanced level instruction (no lengthy explanations) for constructing a P-T pseudosection from equilibria that have been identified from a T-x diagram. The rock composition is that of X=1 "using a T-x diagram to start a new P-T pseudosection” tutorial. The diagram will be calculated from 750-950°C and 4 to 11 kbar. In this tute I will go through calculating only part of the diagram, the rest you can finish on your own. To keep things simple I have not bothered with the sill=ky transition. **This download now contains additional files and instructions for doing the tutorial using thermocalc 3.33*.**

Download PT-pseudosection tutorial 2 for MAC

Download PT-pseudosection tutorial 2 for PC

### Tutorial for calculating mode and composition isopleths (ie contours) (by Richard White)

**Rating: Jedi Knight**

**Date: 29/03/2010**

This tutorial outlines the basics for calculating mode and composition isopleths (contours). The tutorial is based on the composition used for P-T tutorial 1, but uses thermocalc 3.33.

Download isopleth tutorial for MAC

Download isopleth tutorial for PC

### P-T-pseudosection tutorial for mafic rocks (by Johann Diener)

Rating: Jedi Master (these are not the amphiboles you are looking for)

Date: 09/11/2009

This tutorial involves calculating a pseudosection for a metabasaltic composition. While a finished pseudosection is provided, there is no step-by-step instruction, so you should be fairly adept at using thermocalc if you wish to attempt this diagram. The bulk of the text is dedicated to successfully dealing with coexisting phases with identical a-x coding that are separated by solvi.

Download P-T-pseudosection tutorial for mafic rocks for MAC

Download P-T-pseudosection tutorial for mafic rocks for PC

### Tutorial for using the readbulkinfo (rbi) script (by Richard White)

**Rating: Jedi Knight **

**Date: 29/03/2010**

This tutorial illustrates several uses for the readbulkinfo (rbi) script. The rbi script allows the bulk rock composition to be easily set using calculated modes and mineral compositions. The tutorial outlines using this script to firstly remove a proportion of melt from a bulk rock composition and secondly to set an appropriate H2O content at the wet solidus. The tutorial uses thermocalc 3.33 and is based on the bulk rock composition used in P-T tutorial 1.

Download the readbulkinfo tutorial for MAC

Download the readbulkinfo tutorial for PC

### Calculating chemical potential diagrams (by Richard White)

**Rating: Jedi Master/Jedi Grand Master**

**Date: 08/10/2010**

This tutorial illustrates the construction of chemical potential (µ) diagrams. The tutorial starts with a simple µ-µ diagram in MAS and the basics of undertaking calculations involving chemical potentials and extends to understanding three-dimensional µ-µ-µ relationships. The tutorial uses thermocalc 3.33.

Download the chemical potential tutorial for MAC

Download the chemical potential tutorial for PC

## Other Calculation Tutorials to appear soon

- Buffering Calculations tutorial
- T-xCO2 pseudosection tutorial
- re-integrating melt tutorial