Isomekes and Isochors

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The Calc Isomekes tab is for calculating a family of isomekes for the host and the inclusion phases. Isomekes are lines in P-T space along which the fractional volume change of the two phases is equal. 


If a host-inclusion system travels along an isomeke from entrapment, then the pressure in the inclusion remains equal to the external pressure. Therefore isomekes tell you whether to expect under- or over-pressure in the inclusion when the system moves off the entrapment isomeke (Angel et al., 2015; Ferrero and Angel, 2016).



Set a range of starting pressures (at Tmin) from Pmin to Pmax in steps of Pstep.

Set a range of  temperature from Tmin to Tmax in steps of Tstep.


Press the Calculate button to get the results. Warning: the results in the information panel are only updated when you press this button!



A series of isomekes are calculated, each starting from Tmin at each starting pressure, and ending at Tmax.

Starting pressures run from Pmin to Pmax in steps of Pstep


Check the status written by each P,T point. If it says 'ok' there are no problems. If an error is indicated, then there may be a problem in the calculation (such as a convergence error, or you may have gone to a P and T at which one of the EoS is not valid).


You can copy the results from the information window and paste them into a graphics program for plotting, or you can cut and paste them from the log file.




The Isochors tab is for calculating a family of isochors for either  the host or the inclusion phases. It works in the same way as the Calc isomekes tab:



The output lists the P,T points of a series of isochors, and the thermal expansion coefficient and bulk modulus (and their product) at each point.