Skip to main content Accessibility help

Assessing the Blank Carbon Contribution, Isotope Mass Balance, and Kinetic Isotope Fractionation of the Ramped Pyrolysis/Oxidation Instrument at NOSAMS

  • Jordon D Hemingway (a1) (a2), Valier V Galy (a1), Alan R Gagnon (a3), Katherine E Grant (a4), Sarah Z Rosengard (a1) (a2), Guillaume Soulet (a3), Prosper K Zigah (a3) and Ann P McNichol (a3)...


We estimate the blank carbon mass over the course of a typical Ramped PyrOx (RPO) analysis (150–1000°C; 5°C×min–1) to be (3.7±0.6) μg C with an Fm value of 0.555±0.042 and a δ13C value of (–29.0±0.1) ‰ VPDB. Additionally, we provide equations for RPO Fm and δ13C blank corrections, including associated error propagation. By comparing RPO mass-weighted mean and independently measured bulk δ13C values for a compilation of environmental samples and standard reference materials (SRMs), we observe a small yet consistent 13C depletion within the RPO instrument (mean–bulk: μ=–0.8‰; ±1σ=0.9‰; n=66). In contrast, because they are fractionation-corrected by definition, mass-weighted mean Fm values accurately match bulk measurements (mean–bulk: μ=0.005; ±1σ=0.014; n=36). Lastly, we show there exists no significant intra-sample δ13C variability across carbonate SRM peaks, indicating minimal mass-dependent kinetic isotope fractionation during RPO analysis. These data are best explained by a difference in activation energy between 13C- and 12C-containing compounds (13–12 ∆E) of 0.3–1.8 J×mol–1, indicating that blank and mass-balance corrected RPO δ13C values accurately retain carbon source isotope signals to within 1–2‰.


Corresponding author

*Corresponding author. Email:


Hide All
† Current address: Department of Geography, Durham University, South Road, Durham DH1 3LE, UK



Hide All
Berner, U, Faber, E. 1996. Empirical carbon isotope/maturity relationships for gases from algal kerogens and terrigenous organic matter, based on dry, open-system pyrolysis. Organic Geochemistry 24(10–11):947955.
Bianchi, TS, Galy, VV, Rosenheim, BE, Shields, M, Cui, X, Van Metre, P. 2015. Paleoreconstruction of organic carbon inputs to an oxbow lake in the Mississippi River watershed: Effects of dam construction and land use change on regional inputs. Geophysical Research Letters 42:79837991.
Boggs, PT, Rogers, JE. 1990. Orthogonal distance regression. Contemporary Mathematics 112:183194.
Braun, RL, Burnham, AK. 1987. Analysis of chemical reaction kinetics using a distribution of activation energies and simpler models. Energy & Fuels 1:153–161.
Chadwick, OA, Kelly, EF, Hotchkiss, SC, Vitousek, PM. 2007. Precontact vegetation and soil nutrient status in the shadow of Kohala Volcano, Hawaii. Geomorphology 89:7083.
Cramer, B. 2004. Methane generation from coal during open system pyrolysis investigated by isotope specific, Gaussian distributed reaction kinetics. Organic Geochemistry 35:379392.
Currie, LA, Kessler, JD. 2005. On the isolation of elemental carbon (EC) for micro-molar 14C accelerator mass spectrometry: Development of a hybrid reference material for 14C-EC accuracy assurance, and a critical evaluation of the thermal optical kinetic (TOK) EC isolation procedure. Atmospheric Physics and Chemistry 5:28332845.
Dieckmann, V. 2005. Modelling petroleum formation from heterogeneous source rocks: the influence of frequency factors on activation energy distribution and geological prediction. Marine and Petroleum Geology 22:375390.
Fernandez, A, Santos, GM, Williams, EK, Pendergraft, MA, Vetter, L, Rosenheim, BE. 2014. Blank corrections for ramped pyrolysis radiocarbon dating of sedimentary and soil organic carbon. Analytical Chemistry 86:1208512092.
Galimov, EM. 1988. Sources and mechanisms of formation of gaseous hydrocarbons in sedimentary rocks. Chemical Geology 71:7795.
Galy, VV, France-Lanord, C, Lartiges, B. 2008. Loading and fate of particulate organic carbon from the Himalaya to the Ganga-Brahmaputra delta. Geochimica et Cosmochimica Acta 72:17671787.
Kwart, H. 1982. Temperature dependence of the primary kinetic hydrogen isotope effect as a mechanistic criterion. Accounts of Chemical Research 15:401408.
Lopez-Capel, E, Abbott, GD, Thomas, KM, Manning, DAC. 2006. Coupling of thermal analysis with quadrupole mass spectrometry and isotope ratio mass spectrometry for simultaneous determination of evolved gases and their carbon isotopic composition. Journal of Analytical and Applied Pyrolysis 75:8289.
Lopez-Capel, E, Krull, ES, Bol, R, Manning, DAC. 2008. Influence of recent vegetation on labile and recalcitrant carbon soil pools in central Queensland, Australia: evidence from thermal analysis-quadrupole mass spectrometry-isotope ratio mass spectrometry. Rapid Communications in Mass Spectrometry 22:17511758.
McNichol, AP, Gagnon, AR, Jones, GA, Osborne, EA. 1992. Illumination of a black box: analysis of gas composition during graphite target preparation. Radiocarbon 34(3):321329.
McNichol, AP, Jones, GA, Hutton, DL, Gagnon, AR. 1994a. The rapid preparation of seawater ΣCO2 for radiocarbon analysis at the National Ocean Sciences AMS facility. Radiocarbon 36(2):237246.
McNichol, AP, Osborne, EA, Gagnon, AR, Fry, B, Jones, GA. 1994b. TIC, TOC, DIC, DOC, PIC, POC–unique aspects in the preparation of oceanographic samples for 14C-AMS. Nuclear Instruments and Methods in Physics Research B 92:162165.
Mook, WG, van der Plicht, J. 1999. Reporting 14C activities and concentrations. Radiocarbon 41(3):227239.
Nelder, JA, Mead, R. 1965. A simplex method for function minimization. The Computer Journal 7:308313.
Oliphant, TE. 2007. Python for scientific computing. Computing in Science Engineering 9:1020.
Pearson, A, McNichol, AP, Schneider, RJ, von Reden, KF, Zheng, Y. 1998. Microscale AMS 14C measurement at NOSAMS. Radiocarbon 40(1):6175.
Peters, KE. 1986. Guidelines for evaluating petroleum source rock using programmed pyrolysis. AAPG Bulletin 70(3):318329.
Plante, AF, Fernández, JM, Leifeld, J. 2009. Application of thermal analysis techniques in soil science. Geoderma 153:110.
Plante, AF, Beaupré, SR, Roberts, ML, Baisden, T. 2013. Distribution of radiocarbon ages in soil organic matter by thermal fractionation. Radiocarbon 55(2–3):10771083.
Reimer, PJ, Brown, TA, Reimer, RW. 2004. Discussion: reporting and calibration of post-bomb 14C data. Radiocarbon 46(3):12991304.
Rosenheim, BE, Galy, VV. 2012. Direct measurement of riverine particulate organic carbon age structure. Geophysical Research Letters 39:L19703.
Rosenheim, BE, Day, MB, Domack, E, Schrum, H, Benthien, A, Hayes, JM. 2008. Antarctic sediment chronology by programmed‐temperature pyrolysis: methodology and data treatment. Geochemistry, Geophysics, Geosystems 9(4):Q04005.
Rosenheim, BE, Domack, EW, Santoro, JA, Gunter, M. 2013a. Improving Antarctic sediment 14C dating using ramped pyrolysis: an example from the Hugo Island Trough. Radiocarbon 55(1):115126.
Rosenheim, BE, Roe, KM, Roberts, BJ, Kolker, AS, Allison, MA, Johannesson, KH. 2013b. River discharge influences on particulate organic carbon age structure in the Mississippi/Atchafalaya River system. Global Biogeochemical Cycles 27:154166.
Rozanski, K, Stichler, W, Gonfiantini, R, Scott, EM, Beukens, RP, Kromer, B, van der Plicht, J. 1992. The IAEA 14C intercomparison exercise 1990. Radiocarbon 34(3):506519.
Santos, GM, Southon, JR, Griffin, S, Beaupré, SR, Druffel, ER. 2007. Ultra small-mass AMS 14C sample preparation and analyses at KCCAMS/UCI Facility. Nuclear Instruments and Methods in Physics Research B 259:293302.
Schreiner, KM, Bianchi, TS, Rosenheim, BE. 2014. Evidence for permafrost thaw and transport from an Alaskan North Slope watershed. Geophysical Research Letters 41:31173126.
Shah Walter, S, Gagnon, AR, Roberts, M, McNichol, AP, Lardie Gaylord, MC, Klein, E. 2015. Ultra-small graphitization reactors for ultra-microscale 14C analysis at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. Radiocarbon 57(1):109122.
Stuiver, M, Polach, HA. 1977. Discussion: reporting of 14C data. Radiocarbon 19(3):355363.
Subt, C, Fangman, KA, Wellner, JS, Rosenheim, BE. 2016. Sediment chronology in Antarctic deglacial sediments: reconciling organic carbon 14C ages to carbonate 14C ages using Ramped PyrOx. The Holocene 26(2):265273.
Szidat, S, Jenk, TM, Gäggeler, HW, Synal, HA, Hajdas, I, Bonani, G, Saurer, M. 2004. THEODORE, a two-step heating system for the EC/OC determination of radiocarbon (14C) in the environment. Nuclear Instruments and Methods in Physics Research B 223–224:829836.
Tang, Y, Perry, JK, Jenden, PD, Schoell, M. 2000. Mathematical modeling of stable carbon isotope ratios in natural gases. Geochimica et Cosmochimica Acta 64(15):26732687.
Tian, H, Xiao, XM, Wilkins, RWT, Li, XQ, Gan, HJ. 2007. Gas sources of the YN2 gas pool in the Tarim Basin—evidence from gas generation and methane carbon isotope fractionation kinetics of source rocks and crude oils. Marine and Petroleum Geology 24:2941.
White, JE, Catallo, WJ, Legendre, BL. 2011. Biomass pyrolysis kinetics: a comparative critical review with relevant agricultural residue case studies. Journal of Analytical and Applied Pyrolysis 91:133.
Whiteside, JH, Eglinton, TI, Olsen, PE, Cornet, B, McDonald, NG, Huber, P. 2011. Pangean great lake paleoecology on the cusp of the end-Triassic extinction. Palaeogeography, Palaeoclimatology, Palaeoecology 301:117.


Related content

Powered by UNSILO
Type Description Title
Supplementary materials

Hemingway supplementary material
Table S1

 Excel (33 KB)
33 KB

Assessing the Blank Carbon Contribution, Isotope Mass Balance, and Kinetic Isotope Fractionation of the Ramped Pyrolysis/Oxidation Instrument at NOSAMS

  • Jordon D Hemingway (a1) (a2), Valier V Galy (a1), Alan R Gagnon (a3), Katherine E Grant (a4), Sarah Z Rosengard (a1) (a2), Guillaume Soulet (a3), Prosper K Zigah (a3) and Ann P McNichol (a3)...


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.