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Mixing properties of phengitic micas and revised garnet

Aug 30, 2002 Mixing properties of phengitic micas and revised garnet‐phengite thermobarometers R. Coggon University of Cambridge, Department of Earth Sciences, Downing Street, Cambridge CB2 3EQ, UK ([email protected])

Common thermobarometers

Other barometers : Assemblage/Mineral: Si in phengite if phengite in equilibrium with K-feldspar + Mg-biotite + quartz : Al in hornblende if hornblende in equilibrium with quartz + K-feldspar + plagioclase + biotite + magnetite or ilmenite + titanite + melt/fluid (oxygen fugacity and T should also be known)

3. Thermodynamic formulation: thermobarometers based on

Sep 01, 2015 1. Introduction. Empirically calibrated thermometers and barometers are specially well suited for estimating equilibrium P-T conditions in mineral assemblages that involve complex phases whose mixing properties are not fully understood (e.g., McCarthy and Patiño-Docue, 1998, Patiño-Douce, 1993, Schmidt, 1992).Recent empirical calibrations of clinopyroxene-melt and calcic

Practical Thermobarometry Part 3 : Solid Solutions non

Practical Aspects of Mineral Thermobarometry Non-ideal mixing Activity coefficient (one-site substitution) If the mixing is non-ideal, we can introduce a factor (gamma), the activity coefficient, so that where substitution of cation j occurs on n sites per formula unit, e.g. (Ca,Mg,Fe)CO 3, the activity of the j-rich end member i will be a i = (X j j) n

Mixing properties of phengitic micas and revised CORE

Mixing properties of phengitic micas and revised garnet-phengite thermobarometers . the enthalpy of mixing among the end-members muscovite–celadonite–ferroceladonite is nearly ideal, although the Gibbs energies of muscovite–celadonite and muscovite–ferroceladonite solutions are asymmetric due to an asymmetry in the entropy of mixing

Mixing properties and activity-composition relationships

Abstract. Abstract The thermodynamic mixing properties of chlorites in the system MgO-FeO-Al2O3-SiO2-H2O are derived from the experimental study of Baker & Holland (1996) together with observations on the crystal chemistry and natural partitioning behaviour of chlorite and garnet.

"Classical" Thermobarometry SERC

Mar 28, 2019 "Classical" Thermobarometry . Donna Whitney, University of Minnesota . Thermobarometry is the quantitative determination of the temperature and pressure at which a metamorphic or igneous rock reached chemical equilibrium. The term "classical" thermobarometry refers to methods for calculating the P-T conditions of a specific chemical reaction.

Mixing properties of phengitic micas and revised garnet

adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A

Importance of considerations of mixing properties in

Hackler RT, Wood BJ (1989) Experimental determination of Fe and Mg exchange between garnet and olivine and estimation of Fe-Mg garnet mixing properties. Am Mineral (in press) Google Scholar Harley SL (1984a) The solubility of alumina in orthopyroxene coexisting with garnet in FeO-MgO-Al 2 O 3 -SiO 2 and CaO-FeO-MgO-Al 2 O 3 -SiO 2 .

Constraints on the depths and temperatures of basaltic

Mar 15, 2009 However, these thermobarometers should not be applied outside of the range of experimental compositions used in our calibrations (see Fig. 1A and Appendix Fig. 1). Successful application of Eqs. (2),(3) in estimating conditions of melt generation/equilibration in the mantle requires knowledge of the primary magma composition, that is, the

3. Thermodynamic formulation: thermobarometers based on

Sep 01, 2015 1. Introduction. Empirically calibrated thermometers and barometers are specially well suited for estimating equilibrium P-T conditions in mineral assemblages that involve complex phases whose mixing properties are not fully understood (e.g., McCarthy and Patiño-Docue, 1998, Patiño-Douce, 1993, Schmidt, 1992).Recent empirical calibrations of clinopyroxene-melt and calcic

Practical Thermobarometry Part 3 : Solid Solutions non

Practical Aspects of Mineral Thermobarometry Non-ideal mixing Activity coefficient (one-site substitution) If the mixing is non-ideal, we can introduce a factor (gamma), the activity coefficient, so that where substitution of cation j occurs on n sites per formula unit, e.g. (Ca,Mg,Fe)CO 3, the activity of the j-rich end member i will be a i = (X j j) n

Lecture 13: Thermobarometry and thermodynamics Margules

Apply as many different thermobarometers as possible and look for the overlap T = 800 to 850 oC P = 9.3 to 11 kbar 11 Combining thermobarometers and pseudosections 12 0.5 1.0 1.5 2.0 2.5 3.0 400 500 600 700 800 Temperature (˚C) Pressure (GPa) 300 900 1000 Wet peridotite melting curve + cpx + gt + pl + serp + serp, tr + tlc, tr Ol + Sp ± Opx

(PDF) A statistical model of thermodynamic mixing

trieving mixing properties by mathematical programming, it is not possible to assess the robustness of the model. The available mixing properties of garnet are from a lim-

Importance of considerations of mixing properties in

Abstract. A thermodynamic solution model is developed for minerals whose compositions lie in the two binary systems Mg 2 SiO 4-Fe 2 SiO 4 and Mg 2 Si 2 O 6-Fe 2 Si 2 O 6.The formulation makes explicit provision for nonconvergent ordering of Fe 2+ and Mg 2+ between M1 and M2 sites in orthopyroxenes and non-zero Gibbs energies of reciprocal ordering reactions in both olivine and orthopyroxene.

Constraints on the depths and temperatures of basaltic

Mar 15, 2009 However, these thermobarometers should not be applied outside of the range of experimental compositions used in our calibrations (see Fig. 1A and Appendix Fig. 1). Successful application of Eqs. (2),(3) in estimating conditions of melt generation/equilibration in the mantle requires knowledge of the primary magma composition, that is, the

GPT: An excel spreadsheet for thermobarometric

Aug 01, 1996 GPT takes advantage of Excel spreadsheet utilities (e.g. the possibility of entering a large number of data) to calculate 72 thermometers, 59 barometers, two fO 2-meters, thirteen fH 2 O-meters and fourteen XH 2 O-meters, as well as the equations for the calculation of the H 2 O fugacity coefficient corresponding to different mineral assemblages. Each calibration uses expressions by different

Quaternary Solution Model for White Micas Based on Natural

Mixing properties of phengitic micas and revised garnet–phengite thermobarometers. Journal of Metamorphic Geology. 20, 683 –696. De Capitani, C. (1994). Gleichgewichts-Phasendiagramme: Theorie und Software. Berichte der Deutschen Mineralogischen Gesellschaft. Beihefte zum European Journal of

Mixing properties of phengitic micas and revised garnet

Mixing properties for muscovite–celadonite–ferroceladonite solid solutions are derived from combining available experimental phase equilibrium data with tabulated thermodynamic data for

Crystal–Melt Relationships and the Record of Deep Mixing

The degree of magma mixing can be defined using the mixing parameter M, which ranges from zero for unmixed to unity for complete mixing of passive tracers (Maclennan, 2008a). M can be calculated as a function of forsterite content using melt inclusion Þ values, which converge towards zero as mixing

XMapTools Computers & Geosciences

Coggon, T. Holland, Mixing properties of phengitic micas and revised garnet-phengite thermobarometers, Journal of Metamorphic Geology, 20 (2002) 683-696. Google Scholar Cross Ref; bib13. R. Cossio, A. Borghi, R. Ruffini, Quantitative modal determination of geological samples based on X-ray multielemental map acquisition, Microscopy and

Principles of Igneous and Metamorphic Petrology by Anthony

Cambridge Core Mineralogy, Petrology and Volcanology Principles of Igneous and Metamorphic Petrology by Anthony Philpotts

Mineral Geothermobarometry SpringerLink

Dec 31, 2018 Eugster HP, Albee AL, Bence AE et al (1972) The two-phase region and excess mixing properties of paragonite-muscovite crystalline solutions. J Petrol 13:147–179 CrossRef Google Scholar Faryad SW, Chakraborty S (2005) Duration of Eo-Alpine metamorphic events obtained from multicomponent diffusion modeling of garnet: a case study from the

W. M. White Geochemistry Chapter 4: Applications of

mixing = ∆S ideal, and therefore where W S = 0. From equation 4.9, we see that W G is independent of temperature for regular solutions. Exam-ples of such solutions include electrolytes with a single, uncoupled, anionic or cationic substitution, e.g., CaCl 2 —CaBr 2, or solid solutions where there is a single substitution in just one site (e

Practical Thermobarometry Part 3 : Solid Solutions

Energy of mixing Chemical potential and Activity. Read about chemical potential and its relationship to other thermodynamic variables in Spear, Ch 6, pp 138-141. The thermodynamic properties of simple substances, such as the end members of solid solution series, can be measured or estimated.

Lecture 13: Thermobarometry and thermodynamics Margules

Apply as many different thermobarometers as possible and look for the overlap T = 800 to 850 oC P = 9.3 to 11 kbar 11 Combining thermobarometers and pseudosections 12 0.5 1.0 1.5 2.0 2.5 3.0 400 500 600 700 800 Temperature (˚C) Pressure (GPa) 300 900 1000 Wet peridotite melting curve + cpx + gt + pl + serp + serp, tr + tlc, tr Ol + Sp ± Opx

W. M. White Geochemistry Chapter 4: Applications of

mixing = ∆S ideal, and therefore where W S = 0. From equation 4.9, we see that W G is independent of temperature for regular solutions. Exam-ples of such solutions include electrolytes with a single, uncoupled, anionic or cationic substitution, e.g., CaCl 2 —CaBr 2, or solid solutions where there is a single substitution in just one site (e

Mineral Geothermobarometry SpringerLink

Dec 31, 2018 Eugster HP, Albee AL, Bence AE et al (1972) The two-phase region and excess mixing properties of paragonite-muscovite crystalline solutions. J Petrol 13:147–179 CrossRef Google Scholar Faryad SW, Chakraborty S (2005) Duration of Eo-Alpine metamorphic events obtained from multicomponent diffusion modeling of garnet: a case study from the

Valid garnet–biotite (GB) geothermometry and garnet

Jun 01, 2006 In their calibration, ideal mixing of Fe–Mg in biotite was assumed. Their data span narrow compositional ranges of minerals, which may not adequately and accurately describe the mixing properties of garnet and biotite, thus it seems that these thermobarometers lose generality in depicting the mixing properties of these mineral phases.

XMapTools Computers & Geosciences

Coggon, T. Holland, Mixing properties of phengitic micas and revised garnet-phengite thermobarometers, Journal of Metamorphic Geology, 20 (2002) 683-696. Google Scholar Cross Ref; bib13. R. Cossio, A. Borghi, R. Ruffini, Quantitative modal determination of geological samples based on X-ray multielemental map acquisition, Microscopy and

Quaternary Solution Model for White Micas Based on Natural

Mixing properties of phengitic micas and revised garnet–phengite thermobarometers. Journal of Metamorphic Geology. 20, 683 –696. De Capitani, C. (1994). Gleichgewichts-Phasendiagramme: Theorie und Software. Berichte der Deutschen Mineralogischen Gesellschaft. Beihefte zum European Journal of

Recalibration of the Garnet–Muscovite (GM) Geothermometer

We have found that the mixing properties of muscovite solid solutions may be sufficiently described as symmetric Fe 2+ –Mg–Al VI ternary solutions, although much more complex activity models have been proposed (e.g. Coggon & Holland, 2002; Keller et al., 2005). Natural metapelitic samples

Crystal–Melt Relationships and the Record of Deep Mixing

The degree of magma mixing can be defined using the mixing parameter M, which ranges from zero for unmixed to unity for complete mixing of passive tracers (Maclennan, 2008a). M can be calculated as a function of forsterite content using melt inclusion Þ values, which converge towards zero as mixing

Principles of Igneous and Metamorphic Petrology by Anthony

Cambridge Core Mineralogy, Petrology and Volcanology Principles of Igneous and Metamorphic Petrology by Anthony Philpotts

U. Rodehorst Æ M.A. Carpenter Æ T. Boffa Ballaran C.A

Local structural heterogeneity, mixing behaviour and saturation effects are widely used in various geo-thermobarometers. Their properties have been investigated widely, with diffrac-

Syn-deformational melt percolation through a high-pressure

Mar 17, 2020 Coggon R, Holland TJB (2002) Mixing properties of phengitic micas and revised garnet-phengite thermobarometers. J Metamorph Geol 20:683–696. Google Scholar Collins WJ, Sawyer EW (1996) Pervasive granitoid magma transfer through the lower-middle crust during non-coaxial compressional deformation.

References Principles of Igneous and Metamorphic Petrology

Principles of Igneous and Metamorphic Petrology by Anthony Philpotts January 2009

7400R-Revision 2 2 5 José Francisco Molina,Aitor

53 Keywords: thermometry, calcic amphibole, plagioclase, mixing properties, high-grade metamorphic 54 rocks, metaluminous igneous rocks. 55 This is the peer-reviewed, final accepted version for American Mineralogist, published by the Mineralogical Society of America. The published version is subject to change. Cite as Authors (Year) Title.