变质温度压力计

1、Figure 5-1. Stability states. Winter (2001) An Introduction to Igneous and Metamorphic Petrology. Prentice Hall. zzGGVdPSdTT PT PTTPP21112122-=-DG for any reaction = 0 at equilibriumMineralS(J)G (J)V (cm3/mol) Low Albite207.25-3,710,085100.07 Jadeite133.53-2,844,15760.04 Quartz41.36-856,64822.688Fro

2、m Helgeson et al. (1978).Table 27-1. Thermodynamic Data at 298K and0.1 MPa from the SUPCRT DatabaseFigure 27-1. Temperature-pressure phase diagram for the reaction: Albite = Jadeite + Quartz calculated using the program TWQ of Berman (1988, 1990, 1991). Winter (2001) An Introduction to Igneous and M

3、etamorphic Petrology. Prentice Hall. ThusdPdTSV=DDFigure 27-1. Temperature-pressure phase diagram for the reaction: Albite = Jadeite + Quartz calculated using the program TWQ of Berman (1988, 1990, 1991). Winter (2001) An Introduction to Igneous and Metamorphic Petrology. Prentice Hall. GGVdPPPPP211

4、2-=zP x V is a constant at constant TFigure 5-5. Piston-and-cylinder apparatus to compress a gas. Winter (2001) An Introduction to Igneous and Metamorphic Petrology. Prentice Hall. GGVdPPPPP2112-=zGGRTPdPPPPP2112-=zzGGRTPdPPPPP2112-=11xdxx=zlnoodPdTSV=DDFigure 27-2. Pressure-temperature phase diagra

5、m for the reaction muscovite + quartz = Al2SiO5 + K-feldspar + H2O, calculated using SUPCRT (Helgeson et al., 1978). Winter (2001) An Introduction to Igneous and Metamorphic Petrology. Prentice Hall. nnFigure 27-3. Activity-composition relationships for the enstatite-ferrosilite mixture in orthopyro

6、xene at 600oC and 800oC. Circles are data from Saxena and Ghose (1971); curves are model for sites as simple mixtures (from Saxena, 1973) Thermodynamics of Rock-Forming Crystalline Solutions. Winter (2001) An Introduction to Igneous and Metamorphic Petrology. Prentice Hall. All coefficients = 1numbe

7、rs are values for KFigure 27-4. P-T phase diagram for the reaction Jadeite + Quartz = Albite for various values of K. The equilibrium curve for K = 1.0 is the reaction for pure end-member minerals (Figure 27-1). Data from SUPCRT (Helgeson et al., 1978). Winter (2001) An Introduction to Igneous and M

8、etamorphic Petrology. Prentice Hall. T oCInitial X(Fe-Bt)Final X(Fe-Bt)Final X(Fe-Grt)Final (Mg/Fe)GrtFinal (Mg/Fe)BtKT Kelvins1/T KelvinslnK7991.000.7500.9050.1050.3330.31510720.00093-1.1557990.500.7100.8960.1160.4080.28410720.00093-1.2587490.500.6950.8960.1160.4390.26410220.00098-1.3307381.000.730

9、0.9060.1040.3700.28110110.00099-1.2716980.750.7040.9010.1100.4200.2619710.00103-1.3426980.500.6900.8960.1160.4490.2589710.00103-1.3536510.750.6790.9010.1100.4730.2329240.00108-1.4596510.500.6610.8970.1150.5130.2249240.00108-1.4975990.750.6450.9020.1090.5500.1978720.00115-1.6235990.500.6100.8980.1140

10、.6390.1788720.00115-1.7285500.750.6200.9030.1070.6130.1758230.00122-1.7415500.500.5900.8980.1140.6950.1638230.00122-1.8116010.500.5000.8000.2501.0000.2508740.00114-1.3866010.250.3920.7970.2551.5510.1648740.00114-1.8076970.750.5740.8040.2440.7420.3299700.00103-1.1116970.250.4680.7960.2571.1370.226970

11、0.00103-1.487Table 27-2. Experimental results of Ferry and Spear (1978) on a Garnet-Biotite GeothermometerFigure 27-5. Graph of l lnK vs. 1/T (in Kelvins) for the Ferry and Spear (1978) garnet-biotite exchange equilibrium at 0.2 GPa from Table 27-2. Winter (2001) An Introduction to Igneous and Metam

12、orphic Petrology. Prentice Hall. lnKD = -2108 T(K) + 0.781DGP,T = 0 = DH 0.1, 298 - TDS0.1, 298 + PDV + 3 RTlnKDDH P V1SK3RT3Rln-D- DD=oD52 0902 494P MPaTC27319 506 12 943K,.ln=-Figure 27-6. AFM projections showing the relative distribution of Fe and Mg in garnet vs. biotite at approximately 500oC (

13、a) and 800oC (b). From Spear (1993) Metamorphic Phase Equilibria and Pressure-Temperature-Time Paths. Mineral. Soc. Amer. Monograph 1. Figure 27-7. Pressure-temperature diagram similar to Figure 27-4 showing lines of constant KD plotted using equation (27-35) for the garnet-biotite exchange reaction

14、. The Al2SiO5 phase diagram is added. From Spear (1993) Metamorphic Phase Equilibria and Pressure-Temperature-Time Paths. Mineral. Soc. Amer. Monograph 1. Figure 27-8. P-T phase diagram showing the experimental results of Koziol and Newton (1988), and the equilibrium curve for reaction (27-37). Open

15、 triangles indicate runs in which An grew, closed triangles indicate runs in which Grs + Ky + Qtz grew, and half-filled triangles indicate no significant reaction. The univariant equilibrium curve is a best-fit regression of the data brackets. The line at 650oC is Koziol and Newtons estimate of the

16、reaction location based on reactions involving zoisite. The shaded area is the uncertainty envelope. After Koziol and Newton (1988) Amer. Mineral., 73, 216-233 Figure 27-8. P-T diagram contoured for equilibrium curves of various values of K for the GASP geobarometer reaction: 3 An = Grs + 2 Ky + Qtz

17、. From Spear (1993) Metamorphic Phase Equilibria and Pressure-Temperature-Time Paths. Mineral. Soc. Amer. Monograph 1.Wt. % OxidesGarnetBiotiteMuscovite Plagioclase SiO237.2634.2244.5064.93 Al2O321.0318.9734.5022.59 TiO21.230.40 FeO32.4517.500.70 MgO2.469.980.46 MnO6.080.120.02 CaO1.030.010.032.90 N

18、a2O0.271.649.36 K2O7.798.050.45 Total100.3190.0990.30100.23 Si3.005.436.172.84 AlIV2.002.571.831.17 AlVI0.983.81 Ti0.150.04 Fe2.192.320.08 Mg0.302.360.10 Mn0.420.020.00 Ca0.090.000.14 Na0.080.440.83 K1.581.420.03 Fe/(Fe+Mg)0.880.500.46Prp 10An 14Alm 73Ab 83Sps 14Or 3Grs 3 From Hodges and Spear (1982

19、) and Spear (1993).Table 27-3. Mineral Compositions, Formulas, and End-Members for Sample 90A from Mt. Moosilauke, New HampshireCationsFigure 27-10. P-T diagram showing the results of garnet-biotite geothermometry (steep lines) and GASP barometry (shallow lines) for sample 90A of Mt. Moosilauke (Tab

20、le 27-4). Each curve represents a different calibration, calculated using the program THERMOBAROMETRY, by Spear and Kohn (1999). The shaded area represents the bracketed estimate of the P-T conditions for the sample. The Al2SiO5 invariant point also lies within the shaded area. Figure 27-11. P-T pha

21、se diagram calculated by TQW 2.02 (Berman, 1988, 1990, 1991) showing the internally consistent reactions between garnet, muscovite, biotite, Al2SiO5 and plagioclase, when applied to the mineral compositions for sample 90A, Mt. Moosilauke, NH. The garnet-biotite curve of Hodges and Spear (1982) Amer.

22、 Mineral., 67, 1118-1134 has been added. Figure 27-12. Chemically zoned plagioclase and poikiloblastic garnet from meta-pelitic sample 3, Wopmay Orogen, Canada. a. Chemical profiles across a garnet (rim rim). b. An-content of plagioclase inclusions in garnet and corresponding zonation in neighboring

23、 plagioclase. After St-Onge (1987) J. Petrol. 28, 1-22 .P-T-t PathsFigure 27-13. The results of applying the garnet-biotite geothermometer of Hodges and Spear (1982) and the GASP geobarometer of Koziol (1988, in Spear 1993) to the core, interior, and rim composition data of St-Onge (1987). The three

24、 intersection points yield P-T estimates which define a P-T-t path for the growing minerals showing near-isothermal decompression. After Spear (1993). P-T-t PathsFigure 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 shot