Mass-dependent triple oxygen isotope variations in terrestrial materials

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1 Mss-dependent triple oxygen isotope vritions in terrestril mterils Z.D. Shrp, J.A.G. Wostbrock, A. Pck Supplementry Informtion The Supplementry Informtion includes: Frctiontion Equtions The Terrestril Frctiontion Line nd the Definition of 17 O Figures S-1 to S-3 Supplementry Informtion References Frctiontion Equtions Light stble isotope vribility is cused by preferentil enrichment of one or more isotopes between coexisting phses. This cn be due to either equilibrium processes or kinetic processes such s evportion into understurted ir. The fundmentl eqution quntifying frctiontion between two phses nd b is R R = Eq. S-1 b where R is the rtio of the hevy to light isotope, such s 18 O/ 16 O or 17 O/ 16 O. In delt nottion R = R x s Eq. S-2 nd the vlue is given by b = Eq. S b SI-1

2 For the three isotope system, the triple isotope frctiontion exponent -b hs been introduced given by 17 O-b = ( 18 O-b) Eq. S-4 The vlue is not constnt. It chnges with frctiontion process (e.g., kinetic, equilibrium) (Mtsuhis et l., 1978; Young et l., 2002). For equilibrium processes, vries regulrly with temperture (Pck nd Herwrtz, 2014; Shrp et l., 2016). Eq. S-4 cn be recst in liner form s ln( 17 O) = ln( 18 O) Eq. S-5 A similr reltionship cn be mde using linerised delt vlues in per mil nottion, where the (delt-prime) is defined s (Miller, 2002) ' = 1000 ln Eq. S-6 In nottion, -b is given by = Eq. S-7 b ' O ' Ob ' O ' Ob The Terrestril Frctiontion Line nd the Definition of 17 O The 18 O- 17 O vlues of terrestril mterils define the Terrestril Frctiontion Line (TFL) with slope of ~ ½. The generl expression for the TFL is 17 O = RL 18 O + RL Eq. S-8 is replced by RL (RL is for reference line) to signify tht the best-fit slope is strictly empiricl nd does not hve thermodynmic significnce. The RL is the y-intercept of the best fit line, often tken s 0. With ever-higher precision, RL vlues (i.e., the slope of the TFL) hve been refined, with published slopes rnging from to There is no correct TFL slope, s different equilibrium or kinetic processes result in slightly different triple isotope frctiontions. For exmple, meteoric wters fll on trend tht does not overlp with the trend defined by most rocks nd minerls (Luz nd Brkn, 2010; Pck nd Herwrtz, 2014; Pck et l., 2016). A 17 O - 18 O plot of published dt from nturl smples is shown in Figure S-1. The nd vlues differ slightly for different mterils, but virtully ll dt plot exctly on the sme line t the resolution of the figure. In order to better visulise smll devitions from the TFL reference line, the 17 O vlue hs been introduced. The 17 O term is defined s 17 O = 17 O - RL 18 O + RL Eq. S-9 SI-2

3 Often, RL is tken s the best-fit slope for set of dt in 17 O - 18 O spce nd RL is the intercept (generlly ssumed to be 0). In this study, 17 O vlues from different publictions re normlised to VSMOW (rocks nd minerls) nd VSMOW/SLAP2 scle (wters; SLAP2 from (Schoenemnn et l., 2013)) nd derived 17 O to reference line with slope nd zero intercept. Rock smples re normlised to the VSMOW scle with the 17 O vlue of the brodly dopted Sn Crlos Olivine stndrd (SCO) hving 17 O vlue of (Shrp et l., 2016) reltive to RL = (zero intercept). SI-3

4 Supplementry Figures Figure S-1 18 O- 18 O plot of terrestril mterils (Terrestril Frctiontion Line). All dt plot on line with slope of The best fit is strongly nchored by the lrge number of extremely light ice smples from the Vostok core. Excluding these smples, the best-fit line for wters hs slope ( vlue) of Rocks hve slightly lower slope of The best fit to the rock dt is strongly controlled by low temperture mrine sediments. Clerly, there is no single vlue tht is chrcteristic of ll terrestril mterils. (Note: Smples ffected by photochemicl rections re not considered, s they cn fll well off the typicl TFL). Dt from the following sources: (Lndis et l., 2006, 2008, 2010; Rumble et l., 2007, 2013; Luz nd Brkn, 2010; Levin et l., 2014; Pck nd Herwrtz, 2014; Herwrtz et l., 2015; Li et l., 2015; Shrp et l., 2016 nd unpublished dt from UNM lbortory). Crbonte dt re from J. Wostbrock nd were mde by totl fluorintion. Mn-oxide dt re from A. Sntos nd were mde by totl fluorintion. SI-4

5 Figure S-2 Plot of the 18 O- 17 O of chrcteristic mterils with vrious best-fit lines for different mterils. All dt re fit with = Wters hve higher vlue while rocks hve lower vlue. The vlue of is the theoreticl high-temperture limit (see Fig. S-3). SI-5

6 Figure S-3 18 O- 17 O plot using = The informtion is identicl to tht given in Figure 1, but in this plot smple trends hve strong negtive slopes becuse the best-fit vlues for nturl mterils re significntly less thn Consequently, there is generl trend of lower 17 O vlues with incresing 18 O vlues tht overprints the 17 O effect of equilibrium nd kinetic processes. The totl rnge in 17 O is lrger thn in Figure 1, but this is simply result of the choice of not being good fit to the dt. SI-6

7 Supplementry Informtion References Herwrtz, D., Pck, A., Krylov, D., Xio, Y., Muehlenbchs, K., Sengupt, S., Di Rocco, T. (2015) Reveling the climte of snowbll Erth from Δ 17 O systemtics of hydrotherml rocks. Proceedings of the Ntionl Acdemy of Sciences 112, Lndis, A., Brkn, E., Ykir, D., Luz, B. (2006) The triple isotopic composition of oxygen in lef wter. Geochimic et Cosmochimic Act 70, Lndis, A., Brkn, E., Luz, B. (2008) Record of δ 18 O nd 17 O-excess in ice from Vostok Antrctic during the lst 150,000 yers. Geophysicl Reserch Letters 35. Lndis, A., Risi, C., Bony, S., Vimeux, F., Descroix, L., Flourd, S., Bouygues, A. (2010) Combined mesurements of 17 Oexcess nd d-excess in Africn monsoon precipittion: Implictions for evluting convective prmeteriztions. Erth nd Plnetry Science Letters 298, Levin, N.E., Rub, T.D., Duphs, N., Eiler, J.M. (2014) Triple oxygen isotope vritions in sedimentry rocks. Geochimic et Cosmochimic Act 139, Li, S., Levin, N.E., Chesson, L.A. (2015) Continentl scle vrition in 17 O-excess of meteoric wters in the United Sttes. Geochimic et Cosmochimic Act 164, Luz, B., Brkn, E. (2010) Vritions of 17 O/ 16 O nd 18 O/ 16 O in meteoric wters. Geochimic et Cosmochimic Act 74, Mtsuhis, Y., Goldsmith, J.R., Clyton, R.N. (1978) Mechnisms of hydrotherml crystlliztion of qurtz t 250 C nd 15 kbr. Geochimic et Cosmochimic Act 42, Miller, M.F. (2002) Isotopic frctiontion nd the quntifiction of 17 O nomlies in the oxygen three-isotope system: n pprisl nd geochemicl significnce. Geochimic et Cosmochimic Act 66, Pck, A., Herwrtz, D. (2014) The triple oxygen isotope composition of the Erth mntle nd Δ 17 O vritions in terrestril rocks. Erth nd Plnetry Science Letters 390, Pck, A., Tnk, R., Hering, M., Sengupt, S., Peters, S., Nkmur, E. (2016) The oxygen isotope composition of Sn Crlos olivine on the VSMOW2-SLAP2 scle. Rpid Communictions in Mss Spectrometry 30, Rumble, D.I., Miller, M.F., Frnchi, I.A., Greenwood, R.C. (2007) Oxygen three-isotope frctiontion lines in terrestril silicte minerls: An inter-lbortory comprison of hydrotherml qurtz nd eclogitic grnet. Geochimic et Cosmochimic Act 71, Rumble, D., Bowring, S., Iizuk, T., Komiy, T., Leplnd, A., Rosing, M.T., Ueno, Y. (2013) The oxygen isotope composition of Erth's oldest rocks nd evidence of terrestril mgm ocen. Geochemistry, Geophysics, Geosystems 14, Schoenemnn, S.W., Schuer, A.J. nd Steig, E.J. (2013) Mesurement of SLAP2 nd GISP δ 17 O nd proposed VSMOW-SLAP normliztion for δ 17 O nd 17 Oexcess. Rpid Communictions in Mss Spectrometry 27, Shrp, Z.D., Gibbons, J.A., Mltsev, O., Atudorei, V., Pck, A., Sengupt, S., Shock, E.L., Knuth, L.P. (2016) A clibrtion of the triple oxygen isotope frctiontion in the SiO2 - H2O system nd pplictions to nturl smples. Geochimic et Cosmochimic Act 186, Young, E.D., Gly, A., Nghr, H. (2002) Kinetic nd equilibrium mss-dependent isotope frctiontion lws in nture nd their geochemicl nd cosmochemicl significnce. Geochimic et Cosmochimic Act 66, SI-7

Mass-dependent triple oxygen isotope variations in terrestrial materials

2018 The Authors Published by the European Association of Geochemistry Mass-dependent triple oxygen isotope variations in terrestrial materials Z.D. Sharp 1, J.A.G. Wostbrock 1, A. Pack 2 Abstract doi: