I am a sedimentary and organic geochemist. I focus on the redox evolution of the Earth, specializing in biogeochemical cycling. I use a range of geochemical tools, but focus on the stable isotopes of nitrogen, carbon and sulfur, with a particular interest in compound-specific, stable isotope techniques. My research interests span the spectrum of geologic time from the Archean to modern systems. Current I am working principally on the Cretaceous and Neoproterozoic with and eye toward understanding future global change.

Renovations for the new stable isotope lab are complete and will house lab space for preparation and instrumentation for compound-specific carbon, nitrogen and sulfur isotope analyses.

Sample preparation facilities will be housed in a class 10000 clean lab with HEPA-filtered air supply. Two large HEPA-filtered laminar flow exhaust Isolation Cabinets (Patent Pending) capable of class 10 chemistry will be used for acid digestions (kerogen and pyrite), organic extractions, and preparative chromatography.

Instrumentation space includes a new Isoprime 100 continuous flow stable isotope mass spectrometer with Isoprime Trace Gas module as well as an Elementar varioIsotope elemental analyzer for N2, CO2, and SO2.

High-performance liquid chromatography-mass spectrometry (HPLC-MS) will be the focus of our organic geochemistry endeavors. I will be identifying a vendor for the liquid chromatography instrumentation and will be seeking outside funding for an ion-trap, multi-stage mass spectrometer in the near future.

DeMott, LM, Napieralski, SA, Junium, CK, Teece, M, and Scholz, CA, 2019, Microbially influenced lacustrine carbonates: A comparison of late Quaternary Lahontan tufa and modern thrombolite from Fayetteville Green Lake, NY, Geobiology, 00:1–20, https://doi.org/10.1111/gbi.12367

Mettam, C., Zerkle, A. L., Claire, M. W., Prave, A. R., Poulton, S. W. & Junium, C. K., Anaerobic nitrogen cycling on a Neoarchaean ocean margin. Dec 1 2019, In : Earth and Planetary Science Letters. 527, 115800.

Yang, J., Junium, C.K., Grassineau, N.V. et al. Ammonium availability in the Late Archaean nitrogen cycle. Nat. Geosci. 12, 553–557 (2019). https://doi.org/10.1038/s41561-019-0371-1

Judd*, E.J., Ivany, L.C., DeConto, R.M., Halberstadt, A.R.W., Miklus*, N.M., Junium, C.K., Uveges, B.T. (2019) Seasonally resolved proxy data from the Antarctic Peninsula support a heterogeneous middle Eocene Southern Ocean. Paleoceanography and Paleoclimatology, v. 34, pp. 787-799. DOI: 10.1029/2019PA003581

(*student author; †postdoc author)

DeMott LM, Scholz CA and Junium CK, 2019, 8200-year growth history of a Lahontan-age lacustrine tufa deposit, Sedimentology, v. 66, pp. 2169–2190, https://doi.org/10.1111/sed.12579

Junium, C. K., Dickson, A. J. & Uveges, B. T., Perturbation to the nitrogen cycle during rapid Early Eocene global warming. Dec 1 2018, In : Nature Communications. 9, 1, 3186. DOI: 10.1038/s41467-018-05486-w

Uveges, B. T., Teece, M. A., Fulton, J. M. & Junium, C. K., Environmental controls on pigment distributions in the freshwater microbialites of Fayetteville Green Lake. Nov 2018, In : Organic Geochemistry. 125, p. 165-176 12 p. https://doi.org/10.1016/j.orggeochem.2018.08.012

Benjamin T. Uveges, Christopher K. Junium, Diana L. Boyer, Phoebe A. Cohen, James E. Day, Biogeochemical controls on black shale deposition during the Frasnian-Famennian biotic crisis in the Illinois and Appalachian Basins, USA, inferred from stable isotopes of nitrogen and carbon, Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 531, Part A, 2019, https://doi.org/10.1016/j.palaeo.2018.05.031.

Pehr, K., Love, G. D., Kuznetsov, A., Podkovyrov, V., Junium, C. K., Shumlyanskyy, L., Sokur, T. & Bekker, A., et al. Ediacara biota flourished in oligotrophic and bacterially dominated marine environments across Baltica. Nat Commun 9, 1807 (2018). https://doi.org/10.1038/s41467-018-04195-8

Luo G, Junium CK, Izon G, et al. Nitrogen fixation sustained productivity in the wake of the Palaeoproterozoic Great Oxygenation Event. Nat Commun. 2018;9(1):978. Published 2018 Mar 7. https://doi.org/10.1038/s41467-018-03361-2

Nitrogen cycle dynamics in the Late Cretaceous Greenhouse. Junium, C. K., Meyers, S. R. & Arthur, M. A., Jan 1 2018, In : Earth and Planetary Science Letters. 481, p. 404-411 8 p. https://doi.org/10.1016/j.epsl.2017.10.006

Mettam, C., Zerkle, A. L., Claire, M. W., Izon, G., Junium, C. J. & Twitchett, R. J., High-frequency fluctuations in redox conditions during the latest Permian mass extinction. Nov 1 2017, In : Palaeogeography, Palaeoclimatology, Palaeoecology. 485, p. 210-223 14 p. https://doi.org/10.1016/j.palaeo.2017.06.014

Zerkle, A. L., Poulton, S. W., Newton, R. J., Mettam, C., Claire, M. W., Bekker, A. & Junium, C. K., Onset of the aerobic nitrogen cycle during the Great Oxidation Event. Feb 23 2017, In : Nature. 542, 7642, p. 465-467 3 p. https://doi.org/10.1038/nature20826

Junium, C. K., Arthur, M. A. & Freeman, K. H., Compound-specific δ15N and chlorin preservation in surface sediments of the Peru Margin with implications for ancient bulk δ15N records.2015, In : Geochimica et Cosmochimica Acta. 160, p. 306-318 13 p. https://doi.org/10.1016/j.gca.2014.12.018

Zhou, X., Jenkyns, H. C., Owens, J. D., Junium, C. K., Zheng, X. Y., Sageman, B. B., Hardisty, D. S., Lyons, T. W., Ridgwell, A. & Lu, Z., Upper ocean oxygenation dynamics from I/Ca ratios during the Cenomanian-Turonian OAE 2. May 1 2015, In : Paleoceanography. 30, 5, p. 510-526 17 p. https://doi.org/10.1002/2014PA002741

Junium, C. K., Freeman, K. H. & Arthur, M. A., Controls on the stratigraphic distribution and nitrogen isotopic composition of zinc, vanadyl and free base porphyrins through Oceanic Anoxic Event 2 at Demerara Rise. Mar 1 2015, In : Organic Geochemistry. 80, p. 60-71 12 p. https://doi.org/10.1016/j.orggeochem.2014.10.009

Organic-walled microfossil assemblages from glacial and interglacial Neoproterozoic units of Australia and Svalbard. Riedman, L. A., Porter, S. M., Halverson, G. P., Hurtgen, M. T. & Junium, C. K., Jan 1 2014, In : Geology. 42, 11, p. 1011-1014 4 p. https://doi.org/10.1130/G35901.1

Luo, G., Junium, C. K., Kump, L. R., Huang, J., Li, C., Feng, Q., Shi, X., Bai, X. & Xie, S., Shallow stratification prevailed for ~1700 to ~1300 Ma ocean: Evidence from organic carbon isotopes in the North China Craton. Aug 15 2014, In : Earth and Planetary Science Letters. 400, p. 219-232 14 p. DOI:10.1016/J.EPSL.2014.05.020

Kump, L., Junium, C., Arthur, M., Fallick, A., Melezhik, V., Lepland, A., Črne, A., Luo, G., and the FARDEEP Drilling Team, (2011) Isotopic Evidence for the First Massive Oxidation of Organic Matter in Earth History, Science, V334, Issue 6063, pp. 1694-1696. DOI: 10.1126/science.1213999

Cui, Y., Kump, L. R., Ridgwell, A. J., Charles, A. J., Junium, C. K., Diefendorf, A. F., Freeman, K. H., Urban, N. M. & Harding, I. C., Jul 2011, Slow release of fossil carbon during the palaeocene-eocene thermal maximum, In : Nature Geoscience. 4, 7, p. 481-485 5 p. https://doi.org/10.1038/ngeo1179

Junium, C.K., B.J., Keely, K.H., Arthur, M.A., Freeman, (2011) Chlorins in mid-Cretaceous black shales of the Demerara Rise: the oldest known occurrence, Organic Geochemistry.

Polissar, P.J., Fulton, J.F., Junium, C.K., Turich, C.T., Freeman, K.H., (2009) Measurement of 13C and 15N isotopic composition on nanomolar quantities of C and N, Analytic Chemistry, 81, 755-763.

Junium, C.K., Mawson, D.H., Arthur, M.A., Freeman, K.H., Keely, B.J., (2008) Unexpected occurrence and significance of zinc alkyl porphyrins in Cenomanian-Turonian black shales of the Demerara Rise, Organic Geochemistry, 39, 1081-1087.

Zerkle, A.L., Junium, C.K., Canfield, D.E., House, C.H., (2008) Production of 15N depleted biomass during cyanobacterial N2-fixation at high Fe concentrations, Journal of Geophysical Research-Biogeosciences, 113, G03014, doi:10.1029/2007JG000651.

Junium, C.K., Arthur, M.A., (2007) Nitrogen cycling during the Cretaceous, Cenomanian-Turonian Oceanic Anoxic Event II, Geochemistry, Geophysics, Geosystems, 8, 3, doi:10.1029/2006GC001328.

Erbacher, J., D. Mosher, M. Malone, and the ODP Leg 207 Scientific Party, (2004) Drilling probes past carbon cycle perturbations on the Demerara Rise, Eos, 85, 57-63.

Erbacher, J., Mosher, D.C., Malone, M.J., Berti, D., Bice, K.L., Bostock, H., Brumsack, H.-J., Danelian, T., Forster, A., Glatz, C., Heidersdorf, F., Henderiks, J., Janecek, T.R., Junium, C., Le Callonnec, L., MacLeod, K., Meyers, P.A., Mutterlose, H.J., Nishi, H., Norris, R.D., Ogg, J.G., O'Regan, M.A., Rea, B., Sexton, P., Sturt, H., Suganuma, Y., Thurow, J.W., Wilson, P.A., Wise, S.W., Jr., (2004). Proceedings of the Ocean Drilling Program; Demerara Rise; Equatorial Cretaceous and Paleogene Paleoceanographic Transect, Western Atlantic; Covering Leg 207 of the cruises of the drilling vessel JOIDES Resolution; Bridgetown, Barbados, to Rio de Janeiro, Brazil; Sites 1257-1261; 11 January-6 March 2003, Ocean Drilling Program,College Station, TX.