Chapter 27 Thermodynamics of Metamorphic Reactions

1
The Garnet - Biotite geothermometer
lnKD -2108 T(K) 0.781
DGP,T 0 DH 0.1, 298 - TDS0.1, 298 PDV 3
RTlnKD
2

• The Garnet - Biotite geothermometer

3

• The Garnet - Biotite geothermometer

4
GASP barometer
5
GASP barometer
6
Geothermobarometry
7
Geothermobarometry
8
Geothermobarometry
9
Geothermobarometry
P-T-t Paths
10
Geothermobarometry
P-T-t Paths
11
Geothermobarometry
Precision and Accuracy
Figure 27-14. An illustration of precision vs.
accuracy. a. The shots are precise because
successive shots hit near the same place
(reproducibility). Yet they are not accurate,
because they do not hit the bulls-eye. b. The
shots are not precise, because of the large
scatter, but they are accurate, because the
average of the shots is near the bulls-eye. c.
The shots are both precise and accurate. Winter
(2001) An Introduction to Igneous and Metamorphic
Petrology. Prentice Hall.
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Geothermobarometry
Precision and Accuracy