Research Interests

  Sources of Basaltic volcanism:  Basaltic lavas are the most widespread (if indirect) samples of the chemistry of the Earth's mantle.  We have a range of projects involving uses of the isotopic composition of oxygen as a monitor of the presence and abundance of crustal materials (both subducted and from the existing lithosphere) as components to the sources of basaltic lavas.  Oxygen isotopes offer unusual constraints on these issues because oxygen is the only element that is present in nearly equal abundances in most natural solids, melts, and fluids, and the isotopic composition of oxygen is highly sensitive to fractionations that occur at or near the Earth's surface-therefore discriminating between materials that have resided in the crust and those that were produced by differentiation within the mantle.  Recent developments in this program include study of global geochemical variations of mid-ocean ridge basalts, an examination of the impact crustal contamination has on high-magnesium Icelandic basalts, detailed study of the geochemistry of central american arc lavas, and study of samples recently recovered by drilling from deep within Mauna Kea on the  island of Hawaii.

Origin of 'exotic' mantle melts:  Ultramafic mantle nodules frequently contain small inclusions of silicate glass that are compositionally exotic when compared to the range of basaltic magmas typically produced by mantle melting.  The origin of these inclusions is uncertain, and perhaps diverse; one plausible origin for some such compositions is by partial melting of subducted crustal rocks and sediments.  We have conducted several studies of the oxygen isotope composition of such melts using ion microprobe methods, turning up evidence of a close relationship of silicic mantle glasses to subducted upper-crustal materials in two suites of subduction-zone related nodules.  This work will continue in the future with comparisons to suites of compositionally exotic melt inclusions from non-subduction zone environments, and testing of these results with alternate methods (e.g., in situ laser fluorination).

Experimental study of oxygen isotope fractionations among minerals and silicate melts:  A large and longstanding body of research has been conducted on the oxygen isotope geochemistry of magmatic rocks.  However, surprisingly little experimental data is available for oxygen isotope fractionations between silicate melts and coexisting minerals or fluids at high temperatures.  Where such fractionations are needed to interpreted measurements of natural samples, they are commonly guessed at based on measured fractionations between phenocrysts and coexisting glass or groundmass in natural lavas.  We are conducting a series of experiments examining oxygen isotope fractionations between diverse natural and synthetic silicate melts and CO2 vapor; when completed and compared with previous experimental study of oxygen isotope fractionations among minerals, this work will provide a framework for more rigorous interpretiation of the oxygen isotope variations among magmatic rocks.
 

  Stable isotope geochemistry of 'cold' environments:  The stable isotopes of light elements are useful for study of the atmospheres and other near-surface volatiles on the earth and other planets.  In many environments of interest (the earth's upper atmosphere, the atmospheres of Mars and the satelites of the outer planets, and comets), fractionation of stable isotopes take place at temperatures far below that at the earth's surface; stable isotope fractionations under such conditions are largely unknown.
    We have recently begun experimental studies of stable isotope fractionations associated with phase changes and adsorption of naturally important volatiles at 'low' temperatures (< 273 C).  These experiments make use of several specially-designed devices (e.g., a digitally controlled helium cryostat).  Much of the early work in this program has been aimed at understanding the stable isotope geochemistry of the martian CO2 cycle and is described in publications listed below; more recent work is aimed at understanding hydrogen isotope fractionations at conditions comparable to those in the earth's upper troposphere, which will improve constraints on the upper-atmospheric water cycle.
    An unexpected outcome of this work has been the discovery that several compounds exhibit isotopic fractionations between condensed and vapor phases at low temperatures that are 'reversed' relative to common expectations (i.e., we find that for these compounds and conditions light isotopes are concentrated in the condensate rather than the vapor phase).  Existing models for the origin of vapor-pressure isotope effects in molecular compounds cannot explain these results in detail, suggesting that there is something 'missing' from our understanding of the physical chemistry of isotopically substituted volatiles.  We are  currently exploring this effect through  study of vapor pressure isotope effects in a set of compounds of variable molecular structure, such that an emperical data base can be accumulated against which physical models for this phenomenon can be compared.

Origin of Clathrates:  Methane clathrates on the sea floor are widely recognized as a major reservoir of reduced carbon in the earth's surface environment and their decomposition may drive rapid greenhouse warming.  The isotopic composition of carbon (and, to a lesser degree, hydrogen and oxygen) provide key constraints for the sources, sinks, and mechanisms of formation for methane trapped in clathrates.  Despite a large and longstanding body of data on the stable isotope compositions of natural methane clathrates, there have been no experimental measurements of the equilibrium fractionations between clathrates and the gaseous species they trap.  We recently began a series of experiments in which methane clathrates are grown under pressure in the laboratory, after which the isotopic compositions of clathrates and  residual gases are measured.  We anticipate that over the next several months these experiments will yield an estimate of the relevant equilibrium fractionations and that this result will provide new insight for understanding the existing record of stable isotope compositions in natural methane clathrates.
 

Global budgets of N2O:  N2O is an atmospheric greenhouse gas broadly comparable to methane in its significance for the earth's radiative budget.  Good evidence exists for the likely sources and sinks of N2O in the surface environment, but the quantitative budget is extremely poorly known.  Stable isotope geochemistry will play a key role in unraveling this budget; we have recently begin an effort to experimentally constrain the isotopic fractionations associated with biogenic production and photolytic destruction of N2O.  The results of this work will be used as constraints to interpret the rapidly growing data base on the isotopic composition of natural N2O.  This project is part of a collaborative study on the N2O cycle led by Dr. Yuk Yung.  Thom Rahn leads work on this project in the geochemistry laboratories.

Invasion of the fossil embryos:  The ** phosphorite in southern China contains phosphatic microfossils of late-Precambrian organisms.  Eric Davidson, of Caltech's division of Biology, has developed an intriguing hypothesis that a subset of these fossils are the remians of embryos of organisms whose decendants would go on to produce the 'Cambrian explosion' of large-bodied animal life forms.  There are many dimensions to be considered in exploring and developing this hypothesis, some of the simplest of which involve characterizing the detailed mineralogy and geochemistry of the deposit and the fossil embryos in particular.  We recently began such an effort, which will include search for fossilized organic matter and examination of geochemical contrasts between fossils and co-existing, morphologically similar phosphatic spherules.

Hydrogen abundance and isotope geochemistry of solids and silicate melts: A large portion of the research in our group over the last several years has been aimed at using oxygen isotope geochemistry as a constraint on crustal recycling and lithospheric contamination in the petrogenesis of mantle-derived melts.  The insights derived from this work could be greatly expanded by comparison of our results with hydrogen abundances and isotope compositions of these same samples, for instance by demonstrating whether recycled water accompanies or is decoupled from subducted silicate rocks.  In addition, there are a set of issues relevant to the petrogenesis of mantle-derived melts which are largely unconstrained by oxygen isotope variations but well constrained by hydrogen isotope variations, for instance the extent and conditions of magma degasing.  There is a long-standing body of work on the hydrogen isotope geochemistry of mantle rocks and basaltic lavas, but this subject has not yet benefited from the revolutions in laser-based extraction of gases and carrier-gas mass spectrometry (although we note that serious effort has been put towards these goals in recent years; e.g., Powell, 1992).  As with the application of these techniques to oxygen isotope geochemistry of mantle rocks and mantle-derived melts, it is to be expected that such advances may improve the overall quality of the data for bulk samples (i.e, due to reduced blanks, ability to analyze small, highly purified samples, and ease of standardization), and provide a precise, in situ technique that complements or surpasses existing ion probe techniques (e..g., Valley et al., 1998).  We are currently putting substantial effort into developing methods appropriate to this work, using equipment described below.

Analytical techniques:  Stable isotope geochemistry has undergone a revolution in analytical techniques in recent years, principally by capitalizing on previous developments in carier gas mass spectrometry, laser-based extraction from geological materials, and ion probe techniques.  Much of the research conducted by our group makes use of these developments:

High-precision laser fluorination:  We have constructed a laser fluorination apparatus designed to maximize the precision of analyses of 18O/16O ratios on ~mg quantities of silicate and oxide minerals and glasses.  This system encorporates an unusually high powered CO2 laser, reduced interior volumes and e-polished stainless steel construction, and a high-vacuum pumping system, and routinely produces measurements of silicate minerals and glass with external precision and accuracy of +-0.02 to 0.03 per mil.

Hydrogen isotope analysis of trace amounts of water:  We have constructed an apparatus for on-line reduction of 1-10 nano-mole quantities of water vapor followed by carier-gas mass spectrometry of evolved H2 gas.  This system will be integral to our work on vapor-pressure isotope effects for H2O at low temperatures and, more importantly, for development of a hydrogen-isotope laser microprobe.

Deep-UV excimer laser ablation:  We have installed a Lamba Physik LPF 220 excimer laser capable of deep-UV (157 nm) laser ablation of geological materials; the beam delivery system for this laser was constructed by Merchantek.  This laser will serve as the 'front end' for in situ laser fluorination of silicates and oxides, and for the development of a hydrogen isotope microprobe.  This laser works at substantially lower wavelength than previous lasers used for these purposes; it is hoped that this difference may improve yields, elemental and isotopic fractionations during ablation, and the range of materials that can be studied.

Ion microprobe analyses of stable isotope ratios:  We don't have a modern ion microprobe (yet), but we have friends who do and over the last 8 years they have let us use them periodically for studies of the stable isotope composition of oxygen and other elements in minerals and silicate glasses.  These studies have included examination of isotopic zonation produced by diffusion and fluid infiltration in crustal rocks, analysis of oxygen isotope ratios in silicate melt inclusions from mantle nodules, and analysis of oxygen and carbon isotope ratios in minerals and glasses from the SNC meteorites ALH84001 and Lafayette.  We have also conducted two studies of instrumental matrix effects in silicates and carbonates; these studies are time-consuming, but required for accurate measurement of compositionally complex phases.

* Finnigan 251 gas source isotope ratio mass spectrometer (donated by Chevron corporation in 1998)
* Finnigan 252 gas source isotope ratio mass spectrometer (purchased in 1990)
* Finnigan Delta + XL gas source isotope ratio mass spectrometer (purchased in 1999; installed 12/99)

* Custom Merchantek 50 Watt CO2 laser and beam delivery system
* Lamba Physik LPF 220 Excimer laser and Merchanek beam delivery system

* Experimental aparatus for on-line laser fluorination
* Experimental aparatus for on-line for water reduction and organic compound pyrolysis
* Experimental aparatus for low-temperature study of volatiles (components of which were custom built by Janus)

* HP-GC 6890 gas chromatograph

* Assorted conventional glass vacuum apparatus for acid-digestion, pyrolysis, reduction, combustion and other gas-handling proceedures.

Publications  (*updates in progress*)

Journal Articles
     Eiler, J.M., Baumgartner, L.P. and Valley, J.W. (1992) Intercrystalline stable isotope diffusion:
         a fast grain boundary model.  Contrib. Mineral. Petrol., v. 112, p. 543-557.
     Eiler, J.M., Valley, J.W. and Baumgartner, L.P. (1993) A new look at stable isotope
         thermometry.  Geochim. Cosmochim. Acta., v. 57, p.  2571-2583.
     Eiler, J.M., Baumgartner, L.P. and Valley, J.W. (1994) FAST GRAIN BOUNDARY:  a
         FORTRAN-77 program for calculating the effects of  retrograde interdiffusion of stable
         isotopes. Comput. Geosci., v. 20, p. 1415-1434.
     Eiler, J.M. and Valley, J.W. (1994) Preservation of pre-metamorphic oxygen isotope ratios in
         meta-igneous rocks from the Adirondack mountains, NY.  Geochim. Cosmochim. Acta., v. 58,
         p. 5525-5535.
     Eiler, J.M., Valley, J.W., Graham, C.M. and Baumgartner, L.P. (1995) Ion microprobe evidence
         for the mechanisms of stable-isotope retrogression in high-grade metamorphic rocks. Contrib.
         Mineral. Petrol., v. 118, p. 365-378.
     Eiler, J.M., Valley, J.W., Graham, C.M. and Baumgartner, L.P. (1995) The oxygen isotope
         anatomy of a slowly cooled metamorphic rock. American Mineralogist, v. 80, p. 757-764.
     Eiler, J.M., Farley, K., Valley, J.W., Stolper, E.M. Hauri, E., and Craig, H. (1995) Oxygen
         Isotope evidence against bulk recycled sediment in the source of Pitcairn Island lavas.  Nature,
         v.377, p. 138-141.
     Eiler, J.M. , Stolper, E.M. and Valley, J.W. (1996) Oxygen isotope ratios in olivine from the
         Hawaiian scientific drilling project.  Journal of Geophysical Research, v. 101, p. 11,807-11,813.
     Eiler, J.M., Farley, K.A., Valley, J.W., Hofmann, A., and Stolper, E.M. (1996) Oxygen isotope
         constraints on the sources of Hawaiian volcanism.  Earth and Planetary Science Letters, v. 144,
         p. 453-468.
     Eiler, J.M., Graham, C.M., and Valley, J.W. (1996) SIMS Analysis Of Oxygen Isotopes:  Matrix
         Effects In Complex Minerals And Glasses, Chemical Geology, 138, 221-244.
     Eiler, J.M., Farley, K.A., Valley, J.W., Hauri, E., Craig, H., Hart, S.R., and Stolper, E.M. (1997)
         Oxygen isotope variations in ocean island basalt phenocrysts.  Geochim. Cosmochim. Acta, 61,
         2281-2293.
     Eiler, J.M., Mojzsis, S., and Arrhenius, G. (1997) Carbon isotope evidence for life, Nature 386,
         665.
     Valley, J.W., Eiler, J.M., Graham, C.M., Gibson, E., Romanek, C. and Stolper, E.M. (1997)
         Low temperature carbonate concretions in the martian meteorite ALH84001:  Evidence from
         stable isotopes and mineralogy, Science 275, 1633-1638.
     Garcia, M.O., Ito, E., Eiler, J.M., and Pietruszka, A.J. (1997)  Oxygen isotope composition of
         glass and olivine from the Puu Oo eruption of Kilauea volcano, Hawaii reveals a history of
         crustal contamination, Journal of Petrology 39, 809-817.
     Reeder, R.J., Valley, J.W., Graham, C.M. and Eiler, J.M. (1997) Ion microprobe study of
         oxygen isotopic compositions of structurally nonequivalent growth surfaces on synthetic
         calcite.  Geochimica et Cosmochimica Acta 61, 5057-5063
     Eiler, J.M., Farley, K.A., and Stolper, E.M. (1997) Correlated He and Pb isotope variations in
         Hawaiian lavas, Geochimica et Cosmochimica Acta 62, 1977-1984.
     Eiler, J.M., McInnes, B., Valley, J.W., Graham, C.M., and Stolper, E.M. (1998) Oxygen isotope
        evidence for slab-derived fluids in the sub-arc mantle, Nature 393, 777-781.
     Graham, C.M., Valley, J.W., Eiler, J.M., and Wada, H. (1998) Timescales and mechanisms of
         fluid infiltration in a marble: an ion microprobe study.  Contributions to Mineralogy and
        Petrology, 132, 371-389.
     Valley, J.W., Graham, C.M., Harte, B., Eiler, J.M. and Kinny, P.D. (1998) Ion microprobe analysis
         of oxygen, carbon and hydrogen isotope ratios, M.A. McKibben and W.C. Shanks (eds.),
        Applications of Microanalytical Techniques to Understanding Mineralizing Processes, SEG Reviews
        in Economic Geology, Vol. 7, 73-98.
     Foster, C. T., Reagan, M. K., Kennedy, G. S., Smith, G. A., White, C. A., Eiler, J. M. and Rougvie,
        J. R. (1999) Insights into the Proterozoic geology of the Park Range, Colorado, in Karlstrom,
        Karl E. (editor), Lithospheric structure and evolution of the Rocky Mountains; Part II, Rocky
        Mountain Geology 34, 7-20.
LPSC 1999
     Eiler, J.M., Crawford, A., Elliott, T., Farley, K.A., Valley, J.W. and Stolper, E.M. (2000) Oxygen
        isotope geochemistry of oceanic arcs, Journal of Petrology 41, 229-256.
     Eiler, J.M., Schiano, P., Kitchen, N. and Stolper E.M. (2000) Oxygen-isootpe evidence for recycled
        crust in the sources of mid-ocean-ridge basalts, Nature, in press (2/2000)
     Eiler, J.M., Rahn, T., and Kitchen, N. (2000) Experimental constraints on the stable-isotope systematics
        of CO2 ice/vapor systems and relevance to the study of Mars.  Geochimica et Cosmochimica Acta,
        in press.
LPSC 2000
     Rahn, T. and Eiler, J.M. (in preparation, 2000) Experimental constraints on the fractionation of 13C/12C
        and 18O/16O ratios of carbon dioxide due to adsorption at conditions relevant to the surface of Mars.
        To be submitted to GCA, 3/2000.
     Eiler, J.M., McKenzie, D. and others (in preparation, 2000) Oxygen isotope evidence for the origin of
        geochemical variations in recent magnesian lavas from Theistareykir, northern Iceland.  To be
        submitted to EPSL spring, 2000

Abstracts
     Eiler, J.M. and Valley, J.W. (1990) Oxygen isotope evidence for the evolution of Adirondack
         granitoids related to anorthosite.  Geol. Soc. Am. abstr. w. prog., v. 22,  A301.
     Eiler, J.M. and Valley, J.W. (1991) Stable isotopic characteristics and magmatic history of
         meta-igneous rocks, Adirondacks, NY.  EOS, v. 72, p. 310.
     Eiler, J.M., Baumgartner, L.P. and Valley, J.W. (1991) Numerical modeling of diffusive
         exchange of stable isotopes in the lithologic setting. Geol. Soc. Am. abstr. w. prog., v.23, A447.
     Eiler, J.M., Valley, J.W. and Baumgartner, L.P. (1992) Oxygen isotope diffusion: applications to
         thermometry and fluid flow.  Geol. Soc. Am. abstr. w. prog., v. 24, A250.
     Eiler, J.M., Valley, J.W. and Graham, C.M. (1993) The relationship between stable isotope
         diffusion, zonation and thermometry:  a case study from the Adirondack mountains, NY.  EOS,
         v. 74, 330-331.
     Eiler, J.M., Valley, J.W., Baumgartner, L.P. and Graham, C.M. (1993) Grain boundary diffusion
         rates in high-grade metamorphic rocks.  Geol. Soc. Am. abstr. w. prog., v. 25.
     Eiler, J.M., Valley, J.W., Graham, C.M. and Baumgartner, L.P. (1994) Stable isotope
         disequilibrium in high-T metamorphic systems.  Min. Soc. winter conference abstracts, p. 21.
     Eiler, J.M., Valley, J.W., Graham, C.M. and Baumgartner, L.P. (1994) The oxygen isotope
         anatomy of a slowly cooled metamorphic rock. Geol. Soc. Am. abstr. w. prog., v. 26.
     Valley, J.W., Eiler, J.M., Kohn, M.J., Spicuzza, M.J., Baumgartner, L.P., Elsenheimer, D., and
         Graham, C.M. (1994) Contrasting styles of oxygen isotope exchange. Min. Mag., v. 58A,
         924-925.
     Eiler, J.M., Farley, K., Stolper, E.M. and Valley (1995) Oxygen isotope constraints on the
         sources of ocean island basalts.  Terra Nostra, 3/1995, p. 34-37
     Eiler, J.M., Farley, K., Stolper, E.M., Valley, J.W. and Craig, H. (1995) Oxygen isotope ratios in
         phenocrysts from Pitcairn island: constraints on recycled sediment in the “EM1” enriched
         mantle. Geol. Soc. Am. abstr. w. prog., v. 27, p. A36.
     Garcia, M., Pietruszka, A.J., Ito, E., and Eiler, J.M. (1995) Oxygen isotope variations in lavas
         from the ongoing Puu Oo eruption of Kilauea volcano, EOS, v. 76, p. F664.
     Eiler, J.M., Farley, K.A., Valley, J.W., Hofmann, A., and Stolper, E.M. (1996) Oxygen isotope
         constraints on the sources of Hawaiian volcanism.  1996 Goldschmidt conference, Heidelberg,
         Germany.
     Eiler, J.M., Stolper, E.M., Farley, K.A., Valley, J.W., and Hofmann, A.W. (1996) Oxygen
         isotope evidence for contamination of Hawaiian lavas, 1996 Chapman Conference:  “Shallow
         level processes in ocean island magmatism:  Distinguishing mantle and crustal signatures”,
         Tenerife.
     Garcia, M., Pietruszka, A.J., Ito, E., and Eiler, J.M. (1996) Oxygen isotopes reveal a history of
         crustal contamination for lavas from the ongoing eruption of Kilauea volcano, Hawaii. 1996
         Chapman Conference:  “Shallow level processes in ocean island magmatism:  Distinguishing
         mantle and crustal signatures”, Tenerife.
     Eiler, J.M., Farley, K.A., and Stolper, E.M. (1996) Coupling of Pb and He Isotope Variations in
         Hawaiian Lavas, EOS, v. 77, p. F811.
     Mukhopadhyay, S., Farley, K.A., Bogue, S.C., and Eiler, J.M., (1996) Loihi-like 3He/4He ratios
         in shield and caldera filling lavas from Kauai, EOS, v. 77, p. F811.
     Garcia, M., Pietruszka, A.J., Eiler, J.M., and Ito, E. (1996) Crustal contamination of historical
         Kilauea volcano magmas:  Evidence from oxygen isotopes of olivine and matrix materials.  EOS,
         v. 77, p. F798.
     Eiler, J.M., McInnes, B., Valley, J.W., Graham, C.M., and Stolper, E.M. (1997) Slab-derived
         fluids in the mantle:  Oxygen isotope evidence from melt inclusions, Keynote lecture,
         Goldschmidt conference 6/97.
     Eiler, J.M.,  Valley, J.W., and Stolper, E.M. (1997) Stable isotopes in ALH84001: an ion
         microprobe study. Meteoritics and Planetary Science, 32A, p. 38 (Meeting: 60th annual meeting
        of the Meteoritical Society)
     Eiler J.M., Valley, J.W., Graham, C.M. and Stolper, E.M. (1997) Oxygen And Carbon Isotope
         Analysis By SIMS:  A Case Study Of The Martian Meteorite, ALH84001, Invited lecture at the
         1997 SIMS XI meeting.
     Eiler, J.M., Valley, J.W. and Graham, C.M. (1997) Standardization of SIMS Analysis Of O and
        C isotope ratios In Carbonates >From ALH84001, Meteoritics and Planetary Sciences, ###
     Eiler, J.M., Farley, K.A., Valley, J.W.and Stolper, E.M. (1997) Oxygen isotope constraints on
         the sources of oceanic arc volcanism:  The Mariana and South Sandwich arcs.  Eos, Transactions,
        American Geophysical Union, 78, p. 825.
     Valley, J.W., Eiler, J.M., Graham, C.M., Gibson, E., and Romanek, C. (1997) Ion Microprobe
         Analysis of Oxygen and Carbon Isotope Ratios in the ALH84001 Meteorite, Meteoritics and
         Planetary Sciences, ###
     Eiler, J.M., Farley, K.A., Valley, J.W. and Stolper, E.M. (1998) Subduction factory meeting; ###
     Eiler, J. M., Valley, J. W., Graham, C. M., Fournelle, J.,  (1998) Geochemistry of carbonates and
        glass in Allan Hills 84001, Meteoritics & Planetary Science, 33, p. A44-A45 (61st Meteoritical Society
        meeting).
     Vicenzi, E. P. and Eiler, J. (1998) Oxygen-isotopic composition and high-resolution secondary ion
        mass spectrometry imaging of Martian carbonate in Lafayette Meteorite,  Meteoritics & Planetary
        Science, 33, p. A159-A160 (61st Meteoritical Society meeting).
     Eiler, J.M. Goldschmidt (1998) ###
     Eiler, J.M. Fall AGU (1998) Invited lecture ###
     Eiler, J.M., Schiano, P., Kitchen, N. and Stolper, E.M. (1999) Goldschmidt,  ###
     Schiano et al.; (1999), Goldschmidt, ###
     Rahn and Eiler, (1999)  Fall AGU, ###
     Eiler (2000) Goldschmidt,  (invited), ###
     Eiler et al., (2000) Goldschmidt (iceland), ###
     Rahn and Eiler (2000) LPSC (adsorption), ###

     Eiler, J.M. (1994) Diffusion of stable isotopes in metamorphic rocks: Theoretical and applied studies.
        Ph.D. thesis, University of Wisconsin, 343 pp.
     Eiler, J.M. (1991) Oxygen isotope studies of Adirondack orthogneiss. M.S. thesis, University of Wisconsin, 128 pp.
     Eiler, J.M. (1989) Metamorphic history of the northern Park range, Colorado:  constraints on the tectonic
        setting of the Fish-Creek-Soda Creek mylonite zone.  B.S. thesis, University of Iowa, 68  pp.
 
 

Group Members
Nami Kitchen, Senior research assistant:  Nami is principally responsible for high-precision laser fluorination measurements and instrument and technique development
    associated with hydrogen isotope measurements and excimer laser ablation.  She also makes the trains run on time and enforces iron discipline in the laboratory through
    various draconian edicts and corporal punishments.
Thom Rahn, Postdoctoral fellow:  Thom leads research efforts on atmospheric and biogenic N2O and contributes substantially to experimental studies of low-temperature
    isotopic fractionations among volatile species, including those involving clathrates.
Irma Apora, Postdoctoral fellow:  Irma leads experimental studies of high-temperature oxygen isotope fractionations among silicate melts and CO2 vapor, as well as a detailed
    study of oxygen isotope variations among central american arc lavas.
Zhengrong Wang, 1st year graduate student:  Wang is conducting a study of oxygen isotope variations among minerals, glasses, and groundmass material in the drill core
    recovered from the second stage of the Hawaiian Scientific Drilling Project.  Just wait till you see what he's found!

Short-term researchers '99/'00:  Jamie Bresson, Gilead Wurman, Dana **, and James Denedy-* are undergaduate students conducting short research projects in support of
    the broader aims outlined above.

Student Opportunities
Good people never go out of style!  The division of geological and planetary sciences at Caltech is always searching for good new students, and the stable isotope laboratories are stretched trying to cover all the projects we find interesting.  Please feel free to contact us at eiler@gps.caltech.edu if you are interested in learning more about the research efforts summarized above and what you can do to pitch in.