Jay Ague

Jay Ague

Henry Barnard Davis Memorial Professor of Earth & Planetary Sciences
Curator-in-Charge of Mineralogy and Meteoritics, Yale Peabody Museum, Associate Editor of American Jourrnal of Science
Earth & Planetary Sciences

Bio

I study fluid flow, chemical reactions, mass transfer, and heat transfer in Earth’s crust and upper mantle, with a focus on the metamorphic and igneous rocks comprising the deep roots of mountain belts. Our research group integrates fieldwork, chemical and isotopic analyses of rocks and minerals, and numerical simulations. Example research areas include: thermobarometry; heat and mass transport by fluid flow through porous and fractured rock; timescales of orogenic events; fluids and arc volcanism; the impact of subsurface fluids on rock rheology and earthquake hazards; geohydrology; the genesis of economic mineral deposits; processes that release and transport greenhouse gases such as carbon dioxide in Earth’s crust; and carbon sequestration.

I have led or participated in geological research expeditions to numerous places around the globe including British Columbia, California, Greece, Italy, New England, New Zealand, Papua New Guinea, Scotland, South Africa, Spitzbergen, and Washington State. I was the Senior Editor of the American Journal of Science from 1998-2008, am currently on the Editorial Boards of Chemical Geology, The Journal of Metamorphic Geology, and the American Journal of Science, and served on the Editorial Board of the journal Geology. I am also Curator-in-Charge of Mineralogy at the Yale Peabody Museum of Natural History, a position encompassing museum exhibits, mineralogical research, and public outreach and education programs.

Education

Honorary Master of Arts Privatum, Yale University

Ph.D., University of California, Berkeley, Geology

M.S., Wayne State University, Detroit, Michigan, Geology

B.S., Wayne State University, Detroit, Michigan, (High Distinction with a Major in Geology)

Courses

G&G 205, Natural Resources and Their Sustainability

G&G220, Petrology and Mineralogy

G&G350/555, Petrogenesis of Mountain Belts

G&G615, Fluid flow and chemical reaction in geologic systems

+Several seminars focusing on current topics in metamorphism and petrology

Research Opportunities

Research in our group currently focuses on two main themes: (1) ultrahigh-temperature metamorphism and (2) tectonic fluxes of carbon and the deep carbon cycle. Each has many potential avenues for exciting field, laboratory, and /or theoretical research projects that can be tailored to student’s interests and goals. 

Ultrahigh-temperature (UHT) regional metamorphic rocks form at extreme temperatures in excess of 900 ºC. Our group has discovered the first known UHT locality in the United States (click here for more information). The field area is in northeastern Connecticut and is characterized by spectacular examples of garnet and aluminosilicate-rich gneisses (Fig. 1). Of particular interest are garnet porphyroblasts with crystallographically-aligned rutile and ilmenite needles (Fig. 2). These formed by exsolution from original Ti-rich UHT garnet during cooling/exhumation. Laboratory investigation of the needles and other petrographic features confirm that the rocks were heated to at least ~1000 ºC, far beyond the temperature limits of normal regional metamorphism. 

UHT metamorphism is a relatively recently recognized phenomenon worldwide. Consequently, many questions remain about what it is and why it happens. Why did the rocks get so hot? At what depths and pressures did UHT metamorphism occur? What was the tectonic setting, and how were the rocks exhumed? When did it happen? Were melts and fluids involved and, if so, did they originate in the crust or the mantle? Our group is actively working on these and related questions. Moreover, we have identified more potential areas of UHT metamorphism in southern New England that require further mapping, sampling, and analysis.

Carbon fluxes from orogenic belts and subduction zones into the shallow hydrosphere and atmosphere are probably the most poorly-constrained contributions to the global geologic carbon cycle. Are collisional orogens and subduction zones net carbon sources or sinks? Does metamorphism release enough CO2 and other C species like CH4 to impact the shallow carbon cycle and global climate?  

Our group is actively studying such questions to better understand how metamorphic processes fit in to the deep and shallow carbon cycles. For example, it has long been held that decarbonation in subduction zones was dominated by simple reactions involving water and CO2. Our recent work shows, however, that large amounts of CaCO3 (aragonite) can actually dissolve in deep subduction zone fluids, releasing far more CO2 than thought possible based on simple devolatilization reactions (Fig. 3; click here for more information). So it’s now critical to examine carbonate-bearing terranes and re-evaluate reaction mechanisms. The ultimate goal is to determine orogenic CO2 fluxes and their impact on other components of the carbon cycle. Field work is ongoing or will be started in a range of field areas, including New England and the Mediterranean region (Greece, Corsica). 

Software and Pseudosections

This site contains some simple Matlab programs that may be useful when computing pseudosections and oxygen fugacity, as well as thermodynamic data files for Theriak-Domino (de Capitani & Petrakakis, 2010). Theriak-Domino is an extremely powerful software package for making pseudosections and performing a range of other thermodynamic calculations.

All codes and input files are free of charge for non-commercial purposes and are to be run at the sole responsibility of the user. Please let me know if you find any bugs.

The Theriak-Domino homepage of Prof. Dr. C.E. de Capitani is here, and a helpful Research Talk site is here.

*References will be at the bottom

Codes

This code corrects the CaO weight percentage in rocks by accounting for the CaO in apatite. It uses the CaO/P2O5 weight ratio of typical fluorapatite, but you can change this in the code.

This code converts the bulk-rock Fe2O3 weight percentage to both FeO and Fe2O3 weight percentages using your input ratio of Fe3+/(Fe2+ + Fe3+). It also corrects the loss on ignition (LOI) value for the oxygen gained when FeO converts to Fe2O3 during ignition.

This code takes bulk-rock weight percentages and calculates molar compositions suitable for pseudosection input, including formats for Theriak-Domino. It provides both Theriak-Domino and Thermocalc ferrous-ferric styles and includes formatting for MnO projected through spessartine.

To use these codes, run apca.m and feloi.m first to get the CaO, FeO, Fe2O3, and corrected LOI contents for the rock. Then, run genmolo2.m to calculate the molar composition.

This code calculates the oxygen fugacity given an input temperature and chemical potential of O2 (mu_O2) for temperatures ranging from 150 to 1200°C. Use Theriak to get the chemical potentials, then input the O2 potential and temperature into this program. It will output the ln(fO2) and log10(fO2) values.

Download Software Here

Theriak-Domino Input Files

These files are essential tools our group uses. They are based on a program called tcds62cid, which was updated in March 2020. This program uses data from Holland and Powell (2011) for calculations. Professor D.K. Tinkham’s original input files served as the basis for tcds62cid.

We’ve made several adjustments and improvements to these files. For example, we updated garnet parameters for mafic systems and made changes to the delG(tran) offset for the margarite endmember in muscovite. All edits we made are marked with “jja” in the files.

Our data files also consider non-ideal mixing of H2O and CO2, as described by Holland & Powell (2003). This is important because H2O-CO2 mixtures behave differently from ideal mixtures, especially at high temperatures and low pressures.

Zoisite and microcline are turned off by default in our files, but you can activate them by removing the comment symbols (the lines beginning with !). Similarly, we deactivate endmember hematite and ilmenite in favor of solid solution models.

To activate or deactivate a solution phase, simply follow these steps:

  • Change “MuNERAL DATA” to “MINERAL DATA”.
  • Change “SuLUTION DATA” to “SOLUTION DATA”.
  • Change “MuRGULES PARAMETER” to “MARGULES PARAMETER”.

The “mafic” files enable models related to mafic melts, amphiboles, and pyroxenes, based on the work of Green et al. (2016). There are two types of pyroxene: CPXo and CPXg. CPXg is suitable for high-temperature mafic systems with melt, while CPXo is used for omphacitic clinopyroxene.

For compositions with higher aluminum content, solution models for certain phases are deactivated.

The “pelitic” files enable models related to felsic melts and aluminous metapelitic solid solutions, along with CPXo for clinopyroxene.

Understanding Ilmenite Models

In these files, there are three types of ilmenite models: ILM, ILM00Mn (default), and ILM00.

  1. ILM: This model includes both manganese (Mn) and magnesium (Mg).
  2. ILM00Mn: This model only considers manganese (Mn).
  3. ILM00: This model excludes both magnesium (Mg) and manganese (Mn).

The reason for these variations is that sometimes the activity model in ilmenite seems to include too much magnesium, especially at high temperatures.

For the ilmenite models to work well, it’s recommended to provide SEEDS. An example of how to do this is provided in the files.

Since many published examples, like those in Green et al. (2016), use ilmenite-hematite mixing without manganese (Mn) or magnesium (Mg), input files using ILM00 are conveniently provided (they have “ilm00” in their filenames).

Additionally, versions of the files without manganese-bearing solid solutions are also available (they have “noMn” in their filenames). These should be used when computing pseudosections in systems without manganese (Mn).

When computing pseudosections in systems without iron(III) oxide (Fe3+), a tiny amount of oxygen can be added to the bulk composition to ensure the activity models work correctly. However, this may increase calculation time and could cause instability if the amount of oxidized iron is very small. Alternatively, Fe3+ can be deactivated in all solution models, but this requires careful consideration and modification of any external solution models that involve Fe3+.

Download Input Data Files Here

References

de Capitani, C. & Petrakakis, K. (2010). The computation of equilibrium assemblage diagrams with Theriak/Domino software. American Mineralogist 95, 1006-1016.

Green, E.C.R., White, R.W., Diener, J.F.A., Powell, R., Holland, T.J.B. et al. (2016). Activity-composition relations for the calculation of partial melting equilibria in metabasic rocks. Journal of Metamorphic Geology 34, 845-869.

Holland, T.J.B. & Powell, R. (2003). Activity–composition relations for phases in petrological calculations: an asymmetric multicomponent formulation. Contributions to Mineralogy and Petrology 145, 492-501.

Holland, T.J.B. & Powell, R. (2011). An improved and extended internally consistent thermodynamic dataset for phases of petrological interest, involving a new equation of state for solids. Journal of Metamorphic Geology 29, 333-383.

White, R.W., Powell, R., Holland, T.J.B., Johnson, T.E. & Green, E.C.R. (2014). New mineral activity-composition relations for thermodynamic calculations in metapelitic systems. Journal of Metamorphic Geology, 32, 261-286.

Contact Info

jay.ague@yale.edu

+1(203) 432-3171

Mailing address: PO Box 208109, New Haven, CT 06520
Street address: 210 Whitney Avenue, New Haven, CT 06511

Curriculum Vitae

Publications

Ague, J.J., 2014, Fluid Flow in the Deep Crust. In Treatise on Geochemistry (eds. H.D. Holland and K.K. Turekian), 2nd Edition, vol 4, Elsevier, Oxford, p. 203-247. PDF

Philpotts, A.R., and Ague, J. J., 2009, Principles of Igneous and Metamorphic Petrology, 2nd Ed., Cambridge University Press, 667 p.

Stewart, E.M., and Ague, J.J., 2020, Pervasive subduction zone devolatilization recylces CO2 into the forearc: Nature Communications, v. 11, 6220.

Tassara, S., Ague, J.J., and Valencia, V., 2020, The deep magmatic cumulate roots of the Acadian orogen, eastern North America: Geology, v. 49.

Li, J.-L., Klemd, R., Huang, G.-F., Ague, J.J., and Gao, J., 2020, Unravelling slab δ34S compositions from in-situ sulfide δ34S studies of high-pressure metamorphic rocks: International Geology Review.

Keller, D.S., and Ague, J.J., 2020, Quartz, mica, and amphibole exsolution from majoritic garnet reveals ultra-deep sediment subduction, Appalachian orogen: Science Advances, v. 6, no. 11.

Vitale Brovarone, A., Tumiati, S., Piccoli, F., Ague, J.J., Connolly, J.A.D., and Beyssac, O., 2020, Fluid-mediated selective degassing of subducting carbonaceous material: Implications for carbon recycling and fluid fluxes at forearc depths. Chemical Geology, v. 549.

Isson, T.T., Planavsky, N.J., Coogan, L., Stewart, E.M., Ague, J.J., Bolton, E.W., Zhang, S., McKenzie, N.R., and Kump, L.R., 2020, Evolution of the global carbon cycle and climate regulation on Earth: Global Biogeochemical Cycles, Cycles, v. 34, e2018GB006061.

Li, J-L., Schwarzenbach, E.M., John, T., Ague, J.J., Huang, F., Gao, J., Klemd, R., Whitehouse, M.J., and Wang, X-S., 2020, Uncovering and quantifying the subduction zone sulfur cycle from the slab perspective: Nature Communications, v. 11:514.

Keller, D.S., and Ague, J.J., 2019, Crystallographic and textural evidence for precipitation of rutile, ilmenite, corundum, and apatite lamellae from garnet: American Mineralogist, v. 104, p. 980-995.

Stewart, E.M., Ague, J.J., Ferry, J.M., Schiffries, C.M., Tao, R-B., Isson, T.T., and Planavsky, N.J., 2019, Carbonation and decarbonation reactions: Implications for planetary habitability: American Mineralogist, v. 104, p. 1369–1380, invited for “Earth in Five Reactions” Special Collection.

Keller, D.S., and Ague, J.J., 2018, High-pressure granulite facies metamorphism (~1.8 GPa) revealed in silica-undersaturated garnet-spinel-corundum gneiss, Central Maine Terrane, Connecticut, U.S.A.: American Mineralogist, v. 103, p. 1851-1868. 

Chu, X., Ague, J.J., Tian, M., Baxter, E.F., Rumble, D. III, and Chamberlain, C.P., 2018, Testing for rapid thermal pulses in the crust by modeling garnet growth-diffusion-resorption profiles in a UHT metamorphic “hot spot”, New Hampshire, USA: Journal of Petrology, v. 59, p. 1939-1964.

Zhang, S., and Ague, J.J., 2018, Degassing of organic carbon during regional metamorphism of pelites, Wepawaug Schist, Connecticut, USA: Chemical Geology: v. 490, p. 30–44.

Stewart, E.M., and Ague, J.J., 2018, Infiltration-driven metamorphism, New England, USA: regional CO2 fluxes and implications for Devonian climate and extinctions: Earth and Planetary Science Letters, v. 489, p. 123-134.

Vitale Brovarone, A., Chu, X., Martin, L., Ague, J.J., Monié, P., Groppo, C., Martinez, I., and Chaduteau, C. 2018, Intra-slab COH fluid fluxes evidenced by fluid-mediated decarbonation of lawsonite eclogite-facies altered oceanic metabasalts: Lithos, v. 304-307, p. 211-229.

Piccoli, F., Vitale Brovarone, A., and Ague, J.J., 2018, Field and petrological study of carbonate metasomatism from lawsonite eclogite-facies terrains, Alpine Corsica: Lithos, v. 304-307, p. 16-37.

Tian, M., Ague, J.J., Chu, X., Baxter, E.F., Dragovic, N., Chamberlain, C.P., and Rumble, D. III, 2018, The potential for metamorphic thermal pulses to develop during compaction-driven fluid flow:  G3,   doi10.1002/2017GC007269.

Chu, X., Ague, J.J., Podladchikov, Y., and Tian, M., 2017, Ultrafast eclogite formation via melting-induced overpressure: Earth and Planetary Science Letters, v. 479, p. 1-17.

Ague, J.J., 2017, Element mobility during regional metamorphism in crustal and subduction zone environments with a focus on the rare earth elements (REE): American Mineralogist, v. 102, p. 1796–1821.

Stewart, E.M., Baxter, E.F., and Ague, J.J., 2017, Initiation and duration of Grampian orogenesis constrained by refined Sm–Nd garnet geochronology of the Ballantrae ophiolite, Scotland: Journal of the Geological Society of London.

Ague, J.J. and Axler, J.A., 2016, Interface coupled dissolution-reprecipitation in garnet from subducted granulites and ultrahigh-pressure rocks revealed by phosphorous, sodium, and titanium zonation: American Mineralogist, v. 101, p. 1696-1699.

Wang, X., Planavsky, N., Reinhard, C.T., Zou, H., Ague, J.J., Wu, Y., Gill, B.C., Schwarzenbach, E.M., and Peucker-Ehrenbrink, B., 2016, Chromium isotope effects associated with subduction-related metamorphism, black shale weathering, and hydrothermal alteration. Geochimica et Cosmochimica Acta: Chemical Geology, v. 423, p. 19-33.

Piccoli, F., Vitale Brovarone, A., Beyssac, O., Martinez, I., Ague, J.J., and Chaduteau, C., 2016, Carbonation by fluid-rock interactions at high-pressure conditions: Implications for carbon cycling in subduction zones: Earth and Planetary Science Letters, v. 445, p. 146-159.

Chu, X., Ague, J.J., Axler, J.A., and Tian, M., 2016, Taconian retrograde eclogite from northwest Connecticut, USA, and its petrotectonic implications: Lithos, v. 240, p. 276-294.  [Invited research article].

Axler, J.A., and Ague, J.J., 2015, Oriented multiphase needles in garnet from ultrahigh-temperature granulites, Connecticut, USA: American Mineralogist, v. 100, p. 2254-2271.

Chu, X. and Ague, J.J., 2015, Analysis of experimental data on divalent cation diffusion kinetics in aluminosilicate garnets with application to timescales of peak Barrovian metamorphism, Scotland: Contributions to Mineralogy and Petrology, v. 170, DOI 10.1007/s00410-015-1175-y.

Hyndman, R.D., McCrory, P.A., Wech, A., Kao, H., and Ague, J.J., 2015, Cascadia Subducting Plate Fluids Channelled to Forearc Mantle Corner: ETS and Silica Deposition: Journal of Geophysical Research, v. 120, p. 4344-4358.

Axler, J.A., and Ague, J.J., 2015, Exsolution halos of rutile or apatite surrounding ruptured inclusions in garnet from UHT and UHP rocks: Journal of Metamorphic Geology, v. 33, p. 829-848.

Ague, J.J., 2014, Subduction goes organic: Nature Geoscience, v. 7, p. 860-861.

Ague, J.J., and Nicolescu, S., 2014, Carbon dioxide released from subduction zones by fluid-mediated reactions: Nature Geoscience, v. 7, p. 355-360.

Tian, M., and Ague, J.J., 2014, The impact of porosity waves on crustal reaction progress and CO2 mass transfer: Earth and Planetary Science Letters, v. 390, p. 80-92.

Ague, J.J., and Carlson, W.D., 2013, Metamorphism as Garnet Sees It: The kinetics of nucleation and growth, equilibration, and diffusional relaxation: Elements, v. 9, p. 439-445.

Baxter, E.F, Caddick, M.J., and Ague, J.J., 2013, Garnet: Common mineral, uncommonly useful: Elements, v. 9, p. 415-419.

Chu, X., and Ague, J.J., 2013, Phase equilibria for graphitic metapelite including solution of CO2 in cordierite and melt: implications for dehydration, partial melting, and graphite precipitation: Journal of Metamorphic Geology, v. 31, p. 843-862.

Cooke, C.A., Hintelmann, H., Ague, J.J., Burger, R., Biester, H., Sachs, J.P., and Engstrom, D.R., 2013, Use and legacy of mercury in the Andes: Environmental Science and Technology, v.47, 4181-4188.

Ague, J.J., Eckert, J.O., Jr., Chu, X., Baxter, E.F., and Chamberlain, C.P., 2013, Discovery of ultrahigh-temperature metamorphism in the Acadian orogen, Connecticut, USA: Geology, v. 41, p. 271-274.

Vorhies, S.H., Ague, J.J., and Schmitt, A.K., 2013, Zircon growth and recrystallization during progressive metamorphism, Barrovian zones, Scotland: American Mineralogist, v. 98, p. 219-230.

Pickering, J., Ague, J.J., Rath, K.A., Heiser, D.M., and Sirch, J.N., 2012, Museum-based Teacher Professional Development: Peabody Fellows in Earth Science: Journal of Geological Education, v. 60, p. 337–349.

Ague, J.J., and Eckert, J.O., Jr., 2012, Precipitation of rutile and ilmenite needles in garnet: Implications for extreme metamorphic conditions in the Acadian Orogen, USA: American Mineralogist, v. 97, p. 840-855.

Vorhies, S.H., and Ague, J.J., 2011, Pressure-temperature evolution of the Barrovian zones, Scotland: Journal of the Geological Society of London, v. 168, p. 1147-1166.

Emmanuel, S., and Ague, J.J., 2011, Impact of nano-size weathering products on the dissolution rates of primary minerals: Chemical Geology, v. 282, p. 11-18.

Ague, J.J., 2011, Extreme channelization of fluid and the problem of element mobility during Barrovian metamorphism: American Mineralogist, v. 96, p. 333-352.

Qiu, L., Rudnick, R.L., Ague, J.J., and McDonough, W.F., 2011, A Li isotopic study of sub-greenschist to greenschist facies metamorphism in an accretionary prism, New Zealand: Earth and Planetary Science Letters, v. 310, 213-221.

Lyubetskaya, T., and Ague, J.J., 2010, Modeling metamorphism in collisional orogens intruded by magmas: I. Thermal evolution: American Journal of Science, v. 310, p. 427-458.

Lyubetskaya, T., and Ague, J.J., 2010, Modeling metamorphism in collisional orogens intruded by magmas: II. Fluid flow and implications for Barrovian and Buchan metamorphism, Scotland: American Journal of Science, v. 310, p. 459-491.

Emmanuel, S. Ague, J.J., and Walderhaug, O., 2010, Evolution of pore size distributions during quartz precipitation in sandstone and the impact of interfacial energy on reaction kinetics: Geochimica et Cosmochimica Acta, v. 74, p. 3539-52.

Bucholz, C.E. and Ague, J.J., 2010, Fluid flow and Al transport during quartz-kyanite vein formation, Unst, Shetland Islands, Scotland: Journal of Metamorphic Geology, v. 28, p. 19-39.

Lyubetskaya, T., and Ague, J.J., 2009, Effect of metamorphic reactions on thermal evolution in collisional orogens: Journal of Metamorphic Geology, v. 27, p. 579-600.

Lyubetskaya, T., and Ague, J.J., 2009, Modeling the magnitudes and directions of regional metamorphic fluid flow in collisional orogens, Journal of Petrology, v. 50, p. 1505-31. doi:10.1093/petrology/egp039. See also erratum published in v. 50, p. 2375.

Emmanuel, S., and Ague, J.J., 2009, Modeling the impact of nano-pores on mineralization in sedimentary rocks: Water Resources Research, v. 45, W04406, doi:10.1029/2008WR007170.

Lancaster, P.J., Baxter, E.F., Ague, J.J., Breeding, C.M., and Owens, T.L., 2008, Synchronous peak Barrovian metamorphism driven by syn-orogenic magmatism and fluid flow in southern Connecticut, USA: Journal of Metamorphic Geology, 26, p. 527-538.

Carson, C.J., and Ague, J.J., 2008, Early-Palaeozoic metasomatism of the Archaean Napier Complex, East Antarctica: Geological Society of London, Special Publications 2008, v. 308, p. 283-316.

Ague, J.J., and Baxter, E.F., 2007, Brief thermal pulses during mountain building recorded by Sr diffusion in apatite and multicomponent diffusion in garnet: Earth and Planetary Science Letters, v. 261, p. 500-516.

Emmanuel, S., and Ague, J.J., 2007, Implications of present-day abiogenic methane fluxes for the early Archean atmosphere: Geophysical Research Letters, v. 34, L15810, doi:10.1029/2007GL030532.

Wilbur, D.E., and Ague, J.J., 2007, Chemical disequilibrium during garnet growth: Monte Carlo simulations of natural crystal morphologies, Reply: Geology, doi:10.1130/G23787Y.1, p. e125.

Ague, J.J., 2007, Models of permeability contrasts in subduction zone melange: Implications for gradients in fluid fluxes, Syros and Tinos Islands, Greece: Chemical Geology, v. 239, p. 217-227.

Wilbur, D.E., and Ague, J.J., 2006, Chemical disequilibrium during garnet growth: Monte Carlo simulations of natural crystal morphologies: Geology, v. 34, p. 689-692.

Masters, R.L., and Ague, J.J., 2005, Regional-scale fluid flow and element mobility in Barrow’s metamorphic zones, Stonehaven, Scotland: Contributions to Mineralogy and Petrology, v. 150, p. 1-18.

Ague, J.J., 2005, Deep crustal metamorphism of south-central Connecticut, in Skinner, B.J., and Philpotts, A.R., eds., New England Intercollegiate Geological Conference, 97th, trip A-5, p. 107-119.

Breeding, C. M., Ague, J. J., and Broecker, M., 2004, Fluid-metasedimentary rock interactions in subduction zone melange: Implications for the chemical composition of arc magmas: Geology, v. 32, p. 1041-44.

Fassoulas, C., Rahl, J. M., Ague, J. J., and Henderson, K., 2004, Patterns and conditions of deformation in the Plattenkalk nappe, Crete, Greece: A preliminary study: Bulletin of the Geological Society of Greece, v. XXXVI/4, p. 1626-35.

Breeding, C. M., Ague, J. J., Grove, M., and Rupke, A. L., 2004, Isotopic and chemical alteration of zircon by metamorphic fluids: U-Pb age depth-profiling of zircon crystals from Barrow’s garnet zone, northeast Scotland: American Mineralogist, v. 89, p. 1067-77.

Bolton, E. W., Rye, D. M., Ague, J. J., and Luttge, A., 2004, Modeling contact metamorphism of siliceous dolomite via kinetic control of overall reactions, in Wanty, R. B., and Seal, R. R., II, editors, Water-Rock Interaction (Proceedings of the 11th International Symposium on Water-Rock Interaction): London, Balkema (a member of Taylor and Francis Group plc), v. 11, p. 269-272.

Ague, J. J., 2003, Fluid infiltration and transport of major, minor, and trace elements during regional metamorphism of carbonate rocks, Wepawaug Schist, Connecticut, USA: American Journal of Science, v. 303, p. 753-816.

Breeding, C. M., Ague, J. J., Broecker, M., and Bolton, E. W., 2003, Blueschist preservation in a retrograded, high-pressure, low-temperature metamorphic terrane, Tinos, Greece: Implications for fluid flow paths in subduction zones: Geochemistry, Geophysics, and Geosystems, v. 4, 9002, doi:10.1029/2002GC000380, 11 p.

Breeding, C. M., and Ague, J. J., 2002, Slab-derived fluids and quartz-vein formation in an accretionary prism, Otago Schist, New Zealand: Geology, v. 30, p. 499-502.

Carson, C. J., Ague, J. J., and Coath, C. D., 2002, U-Pb geochronology from Tonagh Island, East Antarctica: implications for the timing of ultra-high temperature metamorphism of the Napier Complex: Precambrian Research, v. 116, p. 237-263.

Carson C. J., Ague J. J., Grove M., Coath C. D., and Harrison T. M., 2002, U-Pb isotopic behaviour of zircon during upper-amphibolite facies fluid infiltration in the Napier Complex, east Antarctica: Earth and Planetary Science Letters, v. 199, p. 287-310.

Ague, J. J., 2002, Gradients in fluid composition across metacarbonate layers of the Wepawaug Schist, Connecticut, USA: Contributions to Mineralogy and Petrology, v. 143, p. 38-55.

Baxter, E. F., Ague, J. J., and DePaolo, D. J., 2002, Prograde temperature-time evolution in the Barrovian type-locality constrained by Sm/Nd garnet ages from Glen Clova, Scotland: Journal of the Geological Society of London, v. 159, p. 71-82. Note: First author Baxter (Yale, ‘95) won the Journal of the Geological Society of London’s “Young author of the Year” award for this paper in 2002.

Ague, J. J., Baxter, E. F., and Eckert, J. O., Jr., 2001, High fO2 during sillimanite zone metamorphism of part of the Barrovian type locality, Scotland: Journal of Petrology, v. 42, p. 1301-20.

Ague, J. J., 2000, Release of CO2 from carbonate rocks during regional metamorphism of lithologically heterogeneous crust: Geology, v. 28, p. 1123-26.

Masters, R. L., Ague, J. J., and Rye, D. M., 2000, An oxygen and carbon isotopic study of multiple episodes of fluid flow in the Dalradian and Highland Border Complex, Stonehaven, Scotland: Journal of the Geological Society of London, v. 157, p. 367-379.

Ague, J. J., and Rye, D. M., 1999, Simple models of CO2 release from metacarbonates with implications for interpretation of directions and magnitudes of fluid flow in the deep crust: Journal of Petrology, v. 40, p. 1443-62. PDF

Ague, J. J., 1998, Simple models of coupled fluid infiltration and redox reactions in the crust: Contributions to Mineralogy and Petrology, v. 132, p. 180-197.

Poggi, S. H., Skinner, H. C. W., Ague, J. J., and Carter, D., 1998, Using scanning electron microscopy to study mineral deposits in breast tissues: American Mineralogist, v. 83, p. 1122-26.

Ague, J. J., Park, J., and Rye, D. M., 1998, Regional metamorphic dehydration and seismic hazard: Geophysical Research Letters, v. 25, p. 4221-24. PDF

Ague, J. J., 1997, Thermodynamic calculation of emplacement pressures for batholithic rocks, California: Implications for the aluminum-in-hornblende barometer: Geology, v. 25, p. 563-566. PDF

Ague, J. J., 1997, Crustal mass transfer and index mineral growth in Barrow’s garnet zone, Northeast Scotland: Geology, v. 25, p. 73-76. PDF

Ague, J. J. and van Haren, J. L. M., 1996, Assessing metasomatic mass and volume changes using the bootstrap, with application to deep-crustal hydrothermal alteration of marble: Economic Geology, v. 91, p. 1169-82. PDF

Van Haren, J. L. M., Ague, J. J., and Rye, D. M., 1996, Oxygen isotope record of fluid infiltration and mass transfer during regional metamorphism of pelitic schist, south–central Connecticut, USA: Geochimica et Cosmochimica Acta, v. 60, p. 3487 - 3504. PDF

Ague, J. J. and Brandon, M. T., 1996, Regional tilt of the Mt. Stuart batholith, Washington, determined using Al-in-hornblende barometry: Implications for northward translation of Baja British Columbia. Geological Society of America Bulletin, v. 108, p. 471-488. PDF

Ague, J. J., 1995, Deep crustal growth of quartz, kyanite, and garnet into large aperture, fluid-filled fractures, north-eastern Connecticut, USA: Journal of Metamorphic Geology, v. 13, p. 299-314. PDF

Ague, J.J., 1995, Mass transfer during Barrovian Metamorphism of Pelites, south-central Connecticut-Reply. American Journal of Science, v. 295, p. 1025-33.

Ague, J. J., 1994, Mass transfer during Barrovian Metamorphism of Pelites, south-central Connecticut, I: Evidence for composition and volume change: American Journal of Science, v. 294, p. 989 - 1057. PDF

Ague, J. J., 1994, Mass transfer during Barrovian Metamorphism of Pelites, south-central Connecticut, II: Channelized fluid flow and the growth of staurolite and kyanite: American Journal of Science, v. 294, p. 1061 - 1134. PDF

Ague, J. J. and Brandon, M. T., 1992, Tilt and northward offset of Cordilleran batholiths resolved using igneous barometry: Nature, v. 360, p. 146-149. PDF

Ague, J. J., 1991, Evidence for major mass transfer and volume strain during regional metamorphism of pelites: Geology, v. 19, p. 855-858. PDF

Ague, J. J. and Brimhall, G. H., 1989, Geochemical modelling of steady-state fluid flow and chemical reaction during supergene enrichment of porphyry copper deposits: Economic Geology, v. 84, p. 506-528. PDF

Brimhall, G. H., Lewis, C. J., Ague, J. J., Dietrich, W. E., Hampel, J., Teague, T., and Rix, P.,1988, Metal enrichment in bauxites by deposition of chemically mature aeolian dust: Nature, v. 333, p. 819-824. PDF

Ague, J. J. and Brimhall, G. H., 1988, Magmatic arc asymmetry and distribution of Anomalous plutonic belts in the batholiths of California: Effects of assimilation, cratonal thickness and depth of crystallization: Geological Society of America Bulletin, v. 100, p. 912-927. Click here for map of depth of crystallization computed from crystallization pressures, Sierra Nevada and Penisular Ranges batholiths. /sites/default/files/files/Ague/ague_brimhall_2_gsab88.pdfPDF

Ague, J. J. and Brimhall, G. H., 1988, Regional variations in bulk chemistry, mineralogy and the compositions of mafic and accessory minerals in the batholiths of California: Geological Society of America Bulletin, v. 100, p. 891-911. PDF

Ague, J. J. and Brimhall, G. H., 1987, Granites in the batholiths of California: Products of local assimilation and regional scale crustal contamination: Geology, v. 15, p. 63-66.