NASA Logo Jet Propulsion Laboratory California Institute of Technology View the NASA Portal
NASA Banner
NASA Banner
NASA Banner
NASA Banner
JPL Science
JPL Science Division Home
Planetary Science Planetary Science
Earth and Planetary Atmospheres
Geophysics & Planetary Geosciences
Asteroids, Comets & Satellites
Planetary Chemistry and Astrobiology
Planetary Ices
Climate, Oceans and Solid Earth Sciences Climate, Oceans and Solid Earth Sciences
Astrophysics & Space Sciences Astrophysics & Space Sciences
Earth Science Earth Science
Directorate Science Affiliates Directorate Science Affiliates
Open Postdoc Positions Open Postdoc Positions
Brochures Brochures
 Planetary Chemistry and Astrobiology: People
Kenneth Williford's Picture
Jet Propulsion Laboratory
M/S 183-301
4800 Oak Grove Drive
Pasadena, CA 91109
Curriculum Vitae:

Kenneth Williford

Dr. Williford's research is broadly concerned with tracing the flow of biologically important elements (e.g. C, H, O, N, S) through Earth systems. To do this, he uses the tools of "biogeochemistry" - uncovering the chemical traces of life (bio) preserved in rocks (geo) - within the context of astrobiology (the search for life on other planets). Ken works with Earth materials of many different ages: measuring elemental ratios in modern corals to reconstruct sea surface temperature, analyzing organic matter and pyrite preserved in 200 million year old marine sediments to understand a mass extinction that eliminated two-thirds of animal and plant species, or probing the carbon and sulfur preserved in three billion year old fossil bacteria to understand the evolution of microbial metabolism on the early Earth.

In recent years, Dr. Williford has focused on developing analytical techniques to search for signs of life and environment in some of the oldest rocks on Earth. Fossils are very rare in these rocks, and those that do exist are almost always microscopic. In his laboratory at JPL, Ken studies the biogeochemistry of ancient Earth rocks in part to understand how we can apply similar techniques to the search for evidence of life on other planets - in rocks returned to Earth from the surface of Mars, for example.

Dr. Williford runs the JPL Astrobiogeochemistry lab (ABClab), a facility that features a gas chromatograph-mass spectrometer-isotope ratio mass spectrometer (GC-MS-irMS) system with EA (elemental analyzer), capable of bulk carbon and nitrogen isotope analysis of organic matter, bulk sulfur (four-)isotope analysis of sulfides, and on-line structural and compound specific hydrogen or carbon isotope analysis of individual organic compounds. A comprehensive light and electron microscopy facility is also used for petrography supporting in situ isotopic analysis with SIMS. The ABClab is part of the JPL Center for Analysis of Returned Samples (CARS), a cooperative joint facility that enables clean sample preparation and curation, microscopic characterization, and geochemical analysis of ancient terrestrial and extraterrestrial materials.

Interested students or postdocs, especially those with experience in astrobiology and/or biogeochemistry, are encouraged to contact Dr. Williford about potential opportunities.

  • Ph.D. Earth and Space Sciences and Astrobiology, University of Washington, Seattle, Washington (2007)
  • M.S. Geological Sciences, University of Washington, Seattle, Washington (2000)
  • B.S. Natural Resources, University of the South, Sewanee, Tennessee (1998)

Research Interests
    • Archean biosignatures: using detailed petrography and in situ measurements of the elemental and isotopic composition of organic matter and biominerals to resolve ambiguity in the search for evidence of life on the early Earth
    • Microfossils and microbial metabolism: measuring the elemental, molecular, and isotopic composition of fossilized microorganisms to understand microbial metabolism and biosignature preservation
    • Atmospheric oxygenation: using in situ and bulk measurements of carbon and multiple sulfur isotopes to understand changes in the concentration of oxygen in Earth's atmosphere
    • Mass extinctions: understanding the behavior of biogeochemical cycles during the collapse and recovery of the biosphere associated with mass extinction events

Professional Experience
  • Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA (2012 - Present)
    • Research Scientist, Planetary Chemistry and Astrobiology (2012 - Present)
    • Research Scientist, Mars Science Laboratory and Mars 2020 Sample Handling Group (2013 - Present)
  • Research Associate, Department of Geoscience, University of Wisconsin, Madison, WI USA (2010 - 2012)
  • Research Associate, Department of Chemistry, Curtin University, Perth, WA Australia (2007 - 2010)
  • IGERT Fellow, Department of Earth and Space Sciences, University of Washington, Seattle, WA USA (2005 - 2007)
  • Research Assistant, Department of Earth and Space Sciences, University of Washington, Seattle, WA USA (2003 - 2005)

Community Service
  • Imagine Mars, Akira Toki Middle School, Madison, WI (2011)
  • Astrobiology in Your Back Yard, Madison, WI (2011)
  • Astrobiology night at the ballpark, Madison, WI (2010)
  • Bottle Biology, University of Wisconsin (2010 - 2012)
  • Field trip to stromatolites of the Strelley Pool Formation with the high school students of Marble Bar, Western Australia (2008)
  • Discover Smoke Farm: a BioBlitz and celebration of biodiversity in the foothills of the Cascade mountains with students from Seattle, WA

Selected Awards
  • NSF IGERT Astrobiology Fellowship (2005 - 2007)

Selected Publications
  1. Williford, K.H., Grice, K., Holman, A., McElwain, J., 2013. An organic record of terrestrial ecosystem collapse and recovery at the Triassic-Jurassic boundary in East Greenland. Geochimica et Cosmochimica Acta (in press).
  2. Lepot, K., Williford, K.H., Ushikubo, T., Sugitani, K., Mimura, K., Spicuzza, M.J., Valley, J.W., 2013. Texture-specific isotopic compositions in 3.4 Gyr old organic matter support selective preservation in cell-like structures. Geochemica et Cosmochemica Acta 112: 66-86.
  3. Williford, K.H, Ushikubo, T., Schopf, J.W., Lepot, K., Kitajima, K., Valley, J.W., 2013. Preservation and detection of microstructural and taxonomic correlations in the carbon isotopic compositions of individual Precambrian microfossils. Geochimica et Cosmochimica Acta 104: 165-182.
  4. Williford, K.H., Van Kranendonk, M.J., Ushikubo, T., Kozdon, R., Valley, J.W., 2011. Constraining atmospheric oxygen and seawater sulfate concentrations during Paleoproterozoic glaciation: in situ sulfur three-isotope microanalysis of pyrite from the Turee Creek Group, Western Australia. Geochimica et Cosmochimica Acta 75: 5686-5705.
  5. Williford, K.H., Grice, K., Logan, G.A., Chen, J., Huston, D., 2011. The molecular and isotopic effects of hydrothermal alteration of organic matter in the Paleoproterozoic McArthur River Pb/Zn/Ag ore deposit. Earth and Planetary Science Letters 301:382-392.
  6. Aboglila, S., Grice, K., Dawson, D., Williford, K.H., 2010. Use of biomarker distributions and compound specific isotopes of carbon and hydrogen to delineate hydrocarbon characteristics in the East Sirte Basin (Libya). Organic Geochemistry 41:1249-1258.
  7. Zonneveld, J.P., Beatty, T.W., Williford, K.H., Orchard, M.J., McRoberts, C.A., 2010. Stratigraphy and sedimentology of the lower Black Bear Ridge section, British Columbia: candidate for the base-Norian GSSP. Stratigraphy 7(1): 61-82.
  8. Aboglila, S., Grice, K., Trinajstic, K., Snape, C., Williford, K.H., 2010. The significance of 24-norcholestanes, 4-methylsteranes and dinosteranes in oils and source-rocks from East Sirte Basin (Libya). Applied Geochemistry (in press).
  9. Aboglila, S., Grice, K., Trinajstic, K., Dawson, D., Williford, K., 2010. A geochemical evaluation of thermal maturity and depositional paleoenvironments of seven Cretaceous formations from the East Sirte Basin (Libya). LPI Petroleum Research Journal (in press).
  10. Williford, K.H., Foriel, J., Ward, P.D., Steig, E.J., 2009. Major perturbation in sulfur cycling at the Triassic/Jurassic boundary. Geology 37(9): 835-838.
  11. Grice, K., Lu, H. Atahan, P., Asif, M., Hallmann, C., Greenwood, P., Maslen, E., Tulipani, S., Williford, K.H., Dodson, J., 2009. New insights into the origin of perylene in geological samples. Geochimica et Cosmochimica Acta 73(21): 6531-6543.
  12. Ward, P., McRoberts, C., Williford, K. Reply to comment on: "The organic carbon isotopic and paleontological record across the Triassic-Jurassic boundary at the candidate GSSP section at Ferguson Hill, Muller Canyon, Nevada, USA" by Ward et al. (2007). Palaeogeography, Palaeoclimatology, Palaeoecology 273(1-2): 205-206.
  13. Williford, K.H., Ward, P.D., Garrison, G.H., Buick, R., 2007. An extended stable organic carbon isotope record across the Triassic-Jurassic boundary in the Queen Charlotte Islands, British Columbia, Canada. Palaeogeography, Palaeoclimatology, Palaeoecology 244(1-4): 290-296.
  14. Ward, P.D., Garrison, G.H., Williford, K.H., Kring, D., Goodwin, D., Beattie, M., McRoberts, C., 2007. The organic carbon isotopic and paleontological record across the Triassic-Jurassic boundary at the candidate GSSP section at Ferguson Hill, Muller Canyon, Nevada, USA. Palaeogeography, Palaeoclimatology, Palaeoecology 244(1-4): 281-289.

Group Home Page
People in this Group
Group Projects

JPL Privacy Statement Sitemap Email Contact Form