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    Experimental Geochemistry @ the University of Oregon

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    Experimental Geochemistry @ the University of Oregon

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    Experimental Geochemistry @ the University of Oregon

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    Experimental Geochemistry @ the University of Oregon

ABOUT

I am an associate professor in the Department of Earth Sciences at the University of Oregon. My group designs new experimental methods and mathematical models to interpret isotopic and chemical variations in geologic materials. The lab projects we are working on include:

  • Sintering ash to better understand what happens in volcanic conduits
  • Growing calcite and aragonite crystals to better understand past climate
  • Growing quartz crystals to better understand what happens in fractures and fault zones

Our current field areas are:

  • Crater Lake National Park, OR
  • Bishop Tuff, CA
  • Butte porphyry-copper deposit in Butte, MT
  • Mono Craters volcanic field, CA
  • The Little Colorado River, AZ
  • Lake Abert, OR

Images

PEOPLE

team

James Watkins

Associate Professor
CV_2022_June.pdf
team

Umme Fatema

1st year PhD student
team

Qicui Jia

Visiting PhD student
Tsinghua University
team

Ethan McClelland

Undergraduate intern
Fault healing
team

Joey Vierra

Undergraduate intern
Experimental petrology
team

Jane Port

Undergraduate intern
volcanic sintering


FORMER GROUP MEMBERS

team

Laurent Devriendt

Postdoc
co-advised w/NIOZ
team

Ellen Olsen

PhD 2023
Postdoc at Penn State
team

Marisa Acosta

PhD 2020
Postdoc at UNIL
team

Erin Hoxsie

MSc 2018
Lab analyst at Pace Analytical
team

Madison Ball

MSc 2017
Data analyst in Portland
team

Evan Baker

MSc 2015
PhD student at Tufts
team

Eli Bloch

Postdoc 2014-2015
Postdoc at UNIL
team

Eamonn Needham

BSc 2019
PhD student at ASU
team

Molly Pickerel

BSc 2019
PhD student at UNLV
team

Jim Palandri

Research Associate

RESEARCH

Carbonate paleoclimate records

Stable isotopes in carbonate minerals are widely used to infer paleo-environmental conditions. Oxygen isotopes, for example, record the temperature of carbonate formation. Although these types of proxies work in many settings, there are important details that need to be worked out to fully capitalize on stable isotope measurements. We grow calcite and other minerals in the lab from aqueous solution to figure out what environmental variables in addition to temperature are recorded in the oxygen, carbon, and clumped isotope composition of carbonates.


Volcanic textures

Crystal and bubble shapes in magma are sensitive to temperature, pressure, and magma ascent rate. We simulate volcanic conditions in the lab by heating/cooling and compressing/decompressing magma to figure out how textures in volcanic rocks are created by non-observable processes in the subsurface. The photo is a pumice created by undergraduate Eamonn Needham.


Conduit processes

Bubbles are generally thought to grow as magma rises. Measurements on natural samples suggest that the picture is more complicated. We grow bubbles, sinter ash, and study pyroclasts from volcanoes in Oregon and California to better understand what happens in volcanic conduits when magma rises through the shallow crust.


Fault healing and vein formation

Magmatic-hydrothermal fluids in the crust transport and deposit ore metals in some settings, and in other settings, they feed hot water into high-temperature geothermal systems used to produce electricity. Exactly how minerals precipitate in these environments is not well understood because we cannot directly observe the processes. We grow crystals in the lab under controlled conditions so that we can figure out how and where they form in natural hydrothermal systems.


Crystal growth, diffusion, and radioactive decay

A key assumption in many geochronological studies is that minerals retain the parent and daughter nuclides throughout their existence. Diffusive separation of the parent and daughter isotopes, which can occur when a rock is subjected to reheating events or during the initial cooling of a rock, can give rise to apparent ages that can be too old or too young. We applied these principles to understand why Lu-Hf ages of eucrite meteorites from the asteroid Vesta appeared to (erroneously) pre-date the age of the solar system.


Isotope diffusion in solutions, minerals, and melts

The goal of stable isotope geochemistry is to interpret variations in isotopic abundances that are observed in nature. This requires an understanding of how isotopes are separated during diffusion, chemical reactions, and partitioning between phases. We are measuring small differences in the diffusivities of isotopes to figure out how cations diffuse in liquids and to predict where and when diffusion is responsible for stable isotope variations in nature.


Lots of other projects...

We're always going down new rabbit holes and undergrads are encouraged to participate. Current and past undergrads have worked on dendritic crystal growth, travertine formation, the Soret effect, magma decompression experiments, and ash sintering experiments. Many of the projects involve hands-on experience with high-temperature, high-pressure experimental apparatuses and high-tech instrumentation housed in the CAMCOR facility.

PUBLICATIONS

    Manuscripts

  1. Lucarelli, J., Purgstaller, B., Parvez, Z., Watkins, J., Eagle, R., Dietzel, M., and Tripati, A., 2022, Paired Δ47 and Δ48 analyses and model calculations constrain equilibrium, experimentally-manipulated kinetic isotope effects, and mixing effects in calcite, Geochimica et Cosmochimica Acta, in review.
  2. Hoxsie, E., Watkins, J., Gardner, J., and Befus, K., Ash sintering in the presence of a CO2-H2O vapor: Experiments and comparison to natural samples, for Bulletin of Volcanology.
  3. 2024

  4. Jia, Q., Zhang, S., Watkins, J., Huang, Y., and Wang, G., Modelled foraminiferal calcification and strontium partioning in benthic foraminifera helps reconstruct calcifying fluid composition, Nature Communications: Earth and Environment. (pdf reprint)
  5. 2023

  6. Aubin, W., Gardner, J., Watkins, J., and Lloyd, M., 2023, Construction of obsidian during explosive-effusive eruptions: Insights from microlite crystals in obsidian pyroclasts, Frontiers in Earth Science. (pdf reprint)
  7. Parvez, Z., Matamoros, I., Rubi, J., Miguel, K., Elliot, B., Flores, R., Lucarelli, J., Ulrich, R., Eagle, R., Watkins, J., Christensen, J., and Tripati, A., 202x, Paired Δ4748 constrains kinetic effects and timescales in peridotite-associated springs, Geochimica et Cosmochimica Acta, v. 358, p. 77-92. (pdf reprint)
  8. Hosseini, B., Myers, M., Watkins, J., and Harris, M., Are we recording? Putting embayment speedometry to the test using high pressure-temperature decompression experiments, Geochemistry, Geophysics, Geosystems, 18 pages. (pdf reprint)
  9. 2022

  10. Hudak, M., Bindeman, I., Watkins, J., and Lowenstern, J., 2022, Hydrogen isotope fractionation between volcanic glass and water vapor between 175 and 375°C, GCA, v. 337, p. 33-48. (pdf reprint)
  11. Acosta, M., Reed, M. and Watkins, J., 2022, Textures of quartz-molybdenite veins in the Butte, Montana porphyry copper deposit indicate vein strain during deposit formation, Lithos, 19 pages. (pdf reprint)
  12. Watkins, J., and Devriendt, L., 2022, A combined model for kinetic clumped isotope effects in the CaCO3-DIC-H2O system, Geochemistry, Geophysics, Geosystems, v. 23, 34 pages. (pdf reprint)
  13. Watkins, J., Christensen, J., Ryerson, F., and DePaolo, D., 2022, Ca and K isotope fractionation by diffusion in molten silicates: Large concentration gradients are not required to induce large diffusive isotope effects, Isotopic Constraints on Earth System Processes, Geophysical Monograph, 273. (pdf reprint)
  14. Olsen, E. Watkins, J., and Devriendt, L., 2022, Oxygen isotopes of calcite precipitated at high ionic strength and 25°C: CaCO3-DIC fractionation and carbonic anhydrase inhibition. GCA, v. 325, p. 170-186. (pdf reprint)
  15. 2021

  16. Watkins, J., and Antonelli, M., 2021, Beyond equilibrium: Kinetic isotope effects in high-temperature systems, Elements, v. 17, p. 383-388. (pdf reprint)
  17. Devriendt, L., Metzger, E., Olsen, E., Watkins, J., Kaczmarek, K., Nehrke, G., de Nooijer, L., and Reichart, G.-J., 2021, Sodium incorporation into inorganic calcite and implications biogenic carbonates, GCA, v. 314, p. 294-312. (pdf reprint)
  18. Giachetti, T., Trafton, K., Wiejaczka, J., Gardner, J., Watkins, J., Shea, T., and Wright, H., 201x, The products of primary magma fragmentation finally revealed by pumice agglomerates, Geology, v. 29. (pdf reprint)
  19. Christensen, J., Watkins, J., DePaolo, D., Devriendt, L., Conrad, M., Voltolini, M., Brown, S., and Yang, W., Calcium, carbon, and oxygen isotope fractionation accompanying carbonate precipitation from high pH waters at The Cedars, CA, GCA, v. 301, p. 91-115 (pdf reprint)
  20. 2020

  21. Acosta, M., Watkins, J., Reed, M., Donovan, J., and DePaolo, D., 2020, Ti-in-quartz: Evaluating kinetic effects in high temperature crystal growth experiments, Geochimica et Cosmochimica Acta, v. 149, p. 149-167. (pdf reprint)
  22. 2019

  23. Antonelli, M., Mittal, T., McCarthy, A., Tripoli, B., Watkins, J., and DePaolo, D., 2019, Ca isotopes indicated rapid disequilibrium crystal growth in volcanic and subvolcanic systems, PNAS. (pdf reprint)
  24. Gardner, J., Wadsworth, F., Llewllin, E., Watkins, J.M., and Coumans, J., 2019, Experiments and constraints on the origin of obsidian pyroclasts, Bulletin of Volcanology, 81:22. (pdf reprint)
  25. 2018

  26. Burgener, L., Huntington, K., Sletten, R., Watkins, J.M., Quade, J., and Hallet, B., 2018, Clumped isotope constraints on equilibrium formation and kinetic isotope effects in soil carbonates from freezing soils, Geochimica et Cosmochimica Acta, v. 235, p. 402-430. (pdf reprint)
  27. Myers, M., Wallace, P., Wilson, C., Watkins, J.M. and Liu, Y., 2018, Ascent rates of rhyolitic magma at the onset of three caldera forming eruptions, American Mineralogist, v. 103, p. 952-965. (pdf reprint)
  28. Gardner, J., Wadsworth, F., Llewellin, E., Watkins, J.M. and Coumans, J., 2018, Experimental sintering of ash at conduit conditions and implications for the longevity of tuffisites, Bulletin of Volcanology, v. 80(3), article 23. (pdf reprint)
  29. Bloch, E., Watkins, J.M. and Ganguly, J., 2018, Comment on "Reconciliation of the excess 176Hf conundrum in meteorites: Recent disturbances of the Lu-Hf and Sm-Nd isotope systematics” [Geochimica et Cosmochimica Acta 212 (2017) 303-323], Geochimica et Cosmochimica Acta, v. 230, p. 190-192. (pdf reprint)
  30. 2017

  31. Devriendt, L.S., Watkins, J.M. and McGregor, H.V., 2017, Oxygen isotope fractionations in the CaCO3-DIC-H2O system, Geochimica et Cosmochimica Acta, v. 214, p. 115-142. (pdf reprint)
  32. Saenger, C., Gabitov, R., Farmer, J., Watkins, J.M. and Stone, R., 2017, Linear correlations in bamboo coral δ13C and δ18O sampled by SIMS and micromill: Evaluating paleoceanographic potential and biomineralization mechanisms using δ11B and Δ47 variability, Chemical Geology, v. 454, p. 1-14 . (pdf reprint)
  33. Bloch, E., Watkins, J.., and Ganguly, J., 2017, Diffusion kinetics of lutetium in diopside and the effect of thermal metamorphism on Lu-Hf systematics in meteorites, Geochimica et Cosmochimica Acta, v. 204, p. 32-51. (pdf reprint)
  34. Gardner, J.E., Llewellin, E.W., Watkins, J.M. and Befus, K.S., 2017, Formation of obsidian pyroclasts by sintering of ash particles in the volcanic conduit, Earth and Planetary Science Letters, v. 459, p. 252-263. (pdf reprint)
  35. Watkins, J., Gardner, J.E., and Befus, K.S., 2017, Non-equilibrium degassing, regassing, and vapor fluxing in magma feeder systems, Geology, v. 45, no. 2, p. 183-186. (pdf reprint)
  36. Teng, F., Dauphas, N., and Watkins, J., 2017, Non-traditional stable isotopes: Retrospective and prospective, Reviews in Mineralogy and Geochemistry v. 82. (pdf reprint)
  37. Watkins, J., DePaolo, D., and Watson, E.B., 2017, Kinetic fractionation of non-traditional stable isotopes by diffusion and crystal growth reactions, Reviews in Mineralogy and Geochemistry v. 82. (pdf reprint)
  38. 2016

  39. Seligman, A., Bindeman, I., Watkins, J.., and Ross, A., 2016, Water in volcanic glass: From volcanic degassing to secondary hydration, Geochimica et Cosmochimica Acta, v. 191, p. 216-238. (pdf reprint)
  40. Saenger, C., and Watkins, J., 2016, A refined method for calculating paleotemperatures from linear correlations in bamboo coral carbon and oxygen isotopes, Paleoceanography, v. 31, p. 789-799. (pdf reprint)
  41. Gardner, J., Befus, K., Watkins, J., and Clow, T., 2016, Nucleation rates of spherulites in natural rhyolitic lava, American Mineralogist, v. 101, p. 2367-2376. (pdf reprint)
  42. Aster, A., Wallace, P., Moore, L., Watkins, J., Gazel, E., and Bodnar, R., 2016, Reconstructing CO2 concentrations in basaltic melt inclusions from mafic cinder cones using Raman analysis of vapor bubbles, Journal of Volcanology and Geothermal Research, v. 323, p. 148-162. (pdf reprint)
  43. 2015

  44. Watkins, J., and Hunt, J., 2015, A process-based model for non-equilibrium clumped isotope effects in carbonates, Earth and Planetary Science Letters, v. 432, p. 152-165. (pdf reprint)
  45. Befus, K.S., Watkins, J., Gardner, J., Richard, D., Befus, K.M., Miller, N., and Dingwell, D., 2015, Spherulites as in-situ recorders of thermal history in lava flows, Geology, v. 42, no. 7, p. 647-650. (pdf reprint)
  46. 2014

  47. Watkins, J., Hunt, J., Ryerson, F., and DePaolo, D., 2014, The influence of temperature, pH, and growth rate on the δ18O composition of inorganically precipitated calcite, Earth and Planetary Science Letters, v. 404, p. 332-343. (pdf reprint)
  48. Von Aulock, F., Kennedy, B., Schipper,I., Castro, J., Martin, D., Oze, C., Nichols, A., Watkins, J., Wallace, P., Puskar, L., Bégué, F., Tuffen, H., 2014, Advances in Fourier transform infrared spectroscopy of natural glasses: From sample preparation to data analysis, Lithos, v. 206-207, p. 52-64. (pdf reprint)
  49. Watkins, J., Liang, Y., Richter, F., Ryerson, F., and DePaolo, D., 2014, Diffusion of multi-isotopic species in molten silicates, Geochimica et Cosmochimica Acta, v. 139, p. 313-326 (pdf reprint)
  50. 2013

  51. Watkins, J., Nielsen, L., Ryerson, F., and DePaolo, D., 2013, The influence of kinetics on the oxygen isotope composition of calcium carbonate, Earth and Planetary Science Letters, v. 375, p. 349-360. (pdf reprint)
  52. Gardner, J., Befus, K., Watkins, J., Hesse, M., and Miller, N., 2012, Compositional gradients surrounding spherulites in obsidian and their relationship to spherulite growth and cooling, Bulletin of Volcanology. (pdf reprint)
  53. 2008-2012

  54. Watkins, J., Manga, M., and DePaolo, D., 2012, Bubble geobarometry: A record of pressure changes, degassing, and regassing at Mono Craters, California, Geology. (pdf reprint)
  55. Watkins, J., DePaolo, D., Ryerson, F., and Peterson, B., 2011, Influence of liquid structure on diffusive isotope separation in molten silicates and aqueous solutions, Geochimica et Cosmochimica Acta, v. 75, p. 3103-3118. (pdf reprint)
  56. Watkins, J., 2010, Elemental and isotopic separation by diffusion in geological liquids, Ph.D. Dissertation, University of California Berkeley.
  57. Watkins, J., DePaolo, D., Huber, C., and Ryerson, F., 2009, Liquid composition-dependence of calcium isotope fractionation during diffusion in molten silicates, Geochimica et Cosmochimica Acta, v. 73, p. 7341-7359. (pdf reprint)
  58. Richter, F., Watson, E., Mendybaev, R., Dauphas, N., Georg, B., Watkins, J., and Valley, J., 2009, Isotope fractionation of the major elements of molten basalt by chemical and thermal diffusion, Geochimica et Cosmochimica Acta, v. 73, p. 4250-4263. (pdf reprint)
  59. Huber, C., Watkins, J., and Manga, M., 2008, Steady shape of a miscible bubble rising below an inclined wall at low Reynolds numbers, European Journal of Fluid Mechanics B/Fluids, v. 28, p. 405-410. (pdf reprint)
  60. Watkins, J., Manga, M., Huber, C., and Martin, M., 2008, Diffusion-controlled spherulite growth inferred from H2O concentration profiles in obsidian, Contributions to Mineralogy and Petrology, v. 157, p. 163-172. (pdf reprint)


WHY OREGON?

If you're trying to decide which graduate school you'd like to attend, here are some reasons why you should choose the University of Oregon in Eugene.

Experimental geochemistry @ UO

I'm looking for graduate students to join my group. If you're interested in attending graduate school at UO please send me an email with a copy of your CV and a statement of why you're interested in working with me. Our graduate student applicant pool is very competitive and I'm particularly interested in taking students that have ideas of what they'd like to work on and why we'd be a good fit. There are currently no funded postdoctoral positions availale but if you're interested in writing a proposal to come to Oregon please let me know.

DoES @ UO

We're a big department at 20 faculty members and 40 graduate students, but we're not too big. You'll still get regular attention from your advisor, have the chance to interact with all faculty members, and there's a healthy graduate community to support you in your research endeavors. Many of our recent graduates have gone on to prestigious postdocs at national institutions, such as the USGS, or to other top rated Earth science programs while others acquire faculty positions at schools throughout the US.

Eugene

Eugene is a big-small town. You can find world class fly fishing along the Willamette river, rafting swimming or tubing on the McKenzie, golf in Eugene (Laurelwood) or any of the fine courses nearby (I like Diamond Woods and Tokatee). There are local farmers markets in Eugene on the weekends or you can go to the farm if you prefer. Oregon beer is legendary. You'll have the opportunity to choose from a dozen local breweries in town, or if beer doesn't suit your fancy, the Willamette Valley is up and coming a Pinot noir powerhouse, with several wineries within a few miles of town. For a good time, you can also check out the Oregon Country Fair, the Bach Festival, and Saturday market.

Oregon

An hour drive west of Eugene, you'll find the breathtaking Oregon coast where you can dive, fish, surf, and eat local, all in a day trip. An hour to the east are the Cascades. You can see the Three Sisters volcanoes from Eugene and both downhill and cross country skiing are slightly over an hour away. Two hours north, you'll find Portland, OR. A beer, dub-step, and hipster mecca, you'll need to make a pilgrimage north at some point, if not for Portland itself, to ski above the clouds at Mt. Hood or tour the spectacular waterfalls of the Columbia River Gorge. Two plus hours south is Crater Lake National Park. You'll have your choice of stratovolcanoes, from Mt. Shasta in northern California, to Mt. St. Helens just north of the Oregon-Washinton border....there's plenty to climb and study. The Rogue, McKenzie, and Umpqua rivers are also fun to raft and most are available as day trips. If you like to rock climb, you'll find no shortage of places to do so (Smith rock, near Bend, OR, is well known as the place where sport climbing was invented).

CONTACT


James M. Watkins
Associate Professor
Department of Earth Sciences
1272 University of Oregon
Eugene, OR 97403
Office: Cascade 205A
Email: watkins4@uoregon.edu