Table 3.

The ‘MacArgon’ program (adapted for use with the MacOSX operating systems) is used to compute closure temperatures that would apply for cooling through the Argon Partial Retention Zone, for a range of cooling rates, for zero pressure, as well as for the case when a pressure of 10 kbar (100 MPa) was applied. A single sample was analysed (AG03-07) with a value close to the UCLA average obtained if the first two Arrhenius points were discounted, and the ANU average if these points are taken into account, and no violations of the FAP allowed. Only data for the most retentive domains are shown

Closure temperatures using:Fitted using statistical methodFitted using FAP
‘MacArgon’ for MacOSX
Activation energy46.9 kcal mol−173.5 kcal mol−1
Activation volume10 cm310 cm3
Most retentive domains D0/r233.5 s−15.65×105 s−1
100 °C Ma−1, 0 kbar399 °C553 °C
10 °C Ma−1, 0 kbar360 °C514 °C
1 °C Ma−1, 0 kbar325 °C479 °C
100 °C Ma−1, 10 kbar432 °C579 °C
10 °C Ma−1, 10 kbar391 °C539 °C
1 °C Ma−1, 10 kbar354 °C503 °C
D0/r2 for fitted line2.32×105 s−11.34×1012 s−1
100 °C Ma−1, 0 kbar269 °C354 °C
10 °C Ma−1, 0 kbar243 °C332 °C
1 °C Ma−1, 0 kbar219 °C310 °C
100 °C Ma−1, 10 kbar296 °C375 °C
10 °C Ma−1, 10 kbar269 °C351 °C
1 °C Ma−1, 10 kbar244 °C329 °C