Tracing The Hydrologic CyclePrecipitation and climateWith Environmental Isotopes

Environmental IsotopesJan 14 Introduction to the environmental isotopesJan 21 Tracing the water cycle- 18O, 2HJan 28 Groundwater dating - 3HFeb 4 Carbon cycle 13C, RadiocarbonFeb 11 Water cycle, carbon and climate VeizerFeb 25 Nitrogen cycle 15NMar 4 Water and carbon cycles on Mars - FisherMar 11 Crustal fluids 18O, D, 87Sr, 129I and 36ClMar 18 Noble gases Mar 25 Selected topics - 6Li, 10Be, 11BApril 1 PresentationsApril 8 Presentations

Nucleosynthesis of the elements and isotopes

Nucleosynthesis and formation of the elements

Cosmic abundance of the elements

Mass number

Nucleosynthesis

Big Bang ca 12 000 MaSupernova ca 5 000 MaCondensation of matter and formation of the known elements . . .

In the seconds following theBig Bang

Condensation of matter into p and eFormation of the fuel of the stars . . . H et HeT 3 x 109 Kp + e n + v1H + n 2H + g2H + p 3He + g 3He + n 4He + g

Diagramme Hertzprung-Russel

1st Generation Stars - H fusion and production of 4He

1H + 1H 2H + b+ + v0.422 MeV2H + 1H 3He + g 5.493 MeV3He + 3He 4He + 1H + 1H12.859 MeV

2nd Generation Stars(Our sun today)Fusion by CNO reaction

12C + 1H 13N + g13N 13C + b+ + v13C + 1H 14N + g14N + 1H 15O + g15O 15N + b+ + v15N + 1H 12C + 4He

He Fusion in Red Giants (~ 106 to 107 years)

4He + 4He 8Be8Be + 4He 12C + g

12C burning (

End of a Red Giant's life: Si combustion:lasts about 1day

28Si + 4He 32S + g 32S + 4He 36Ar + g 36Ar + 4He 40Ca + g40Ca + 4He 44Ti + g 44Ca + 2b+44Ti + 4He 48Cr + g 48Ti + 2b+48Cr + 4He 52Fe 52Cr + 2b+52Fe + 4He 56Ni + g 56Fe + 2b+ 56Ni / 56Fe + 4He impossible . . .

Nuclear binding energy maximum

maximum at 56Fe after, fusion becomes endothermic nucleosynthesis beyond 56Fe is by neutron capture and by fission of nuclides with Z > 90 (uranium and transuranics)

http://www.chem.uidaho.edu/~honors/nucbind.html

Supernovaand 2nd generation stars

Supernova remnants

Cas A in x-rays (Chandra)

Vela

SN1998bu

Remnant of SN386, with central pulsar (Chandra)

Cygnus Loop (HST): green=H, red=S+, blue=O++

Nucleosynthesis by n and p capture

Fe: producedin the finalstage of fusion

Elements > Fe: neuton activationin supernova

Instable

CNO

Fissionable Elements

F

Na

Mg

Cl

Al

P

K

Ar

V

Ti

Cr

Mn

Co

Equilibriumburning

The Stable Environmental IsotopesIsotope Ratio % natural Reference abundance 2H 2H/1H 0.015VSMOW3He3He/4He0.000138 Atmospheric He13C13C/12C1.11VPDB 15N15N/14N0.366AIR N2 18O18O/16O0.204VSMOW, VPDB34S34S/32S4.21CDT37Cl37Cl/35Cl24.23SMOC

Delta - permil: d - VSMOW

What is the relative enrichment or depletion of 18O in crustal rocks (~0.204%) relative to VSMOW

= 17.4 VSMOW

crustal rocks are enriched in 18O by 17.4 or 1.7% relative to the standard VSMOW

Isotope Ratio Mass Spectrometry

Laser attenuation isotope analyser(Wavelength-Scanned Cavity Ring Down Spectroscopy WS-CRDS) Laser absorptionReads fraction of heavy isotope bondsDirect reading of BOTH 18O and D ratiosDo it in the field!

Los Gatos the original black boxLaser attenuation isotope analyser(Wavelength-Scanned Cavity Ring Down Spectroscopy WS-CRDS) and Picarro nice small footprint

Laser attenuation isotope analyser(Wavelength-Scanned Cavity Ring Down Spectroscopy WS-CRDS) Check out the sample requirements 2 mL.Fill a tray of 100! lots of good data.

Distribution of isotopes in natureIsotope fractionation during reactionRayleigh distillation during reservoir depletion

Isotope fractionation, a

Physico-chemical fractionation

16Owater + 18Ovapor 18Owater + 16Ovapor

Isotope partitioning functions = symmetry valuem = mass of isotopeE = the energy state summed from the zero-point to the energy of the dissociated molecule (Jmole1)k = Boltzmann constant (gas constant per molecule) = n 1.380658 1023 JK1T = thermodynamic temperature K

Diffusive fractionationv = molecular velocity (cm s1)k = Boltzmann constant (gas constant per molecule) = n 1.380658 1023 JK1m = molecular mass (e.g. 7.3665 1026 kg for 12C16O2)T = absolute temperature K

Diffusive FractionationDiffusion in a vacuumDiffusion in aire.g. 13C during CO2 diffusion

UnitsIsotope Enrichment (e)Isotope difference in permil units between two reacting phases at equilibrium

when a is small, then we can use:

UnitsIsotope Separation (D)Isotope difference in permil units between any two phases

_925138763.unknown

For a water vapor exchange at 25C what is the d18O of vapor, where:

water d18Ow = 0.0 VSMOW

For a water vapor exchange at 25C what is the d18O of vapor, where: water d18Ow = 0.0 VSMOW

The fractionation factor (a) is:a18Ow-v = 1.0093

The isotopic enrichment (e):

e18Ow-v = (a1) 103 = 9.3 and e18Ov-w = 9.3

For a water vapor exchange at 25C what is the d18O of vapor, where: water d18Ow = 0.0 VSMOW

e18Ow-v = (a1) 103 = 9.3

d18Ovapor = d18Owater e18Owater-vapor = 0.0 9.3 = 9.3

vapor d18Ov = 9.30 VSMOW

For most reactions in hydrogeology:

d values are typically 50 to +50 a values are close to 1 (0.98 to 1.02) e values are typically 20 to +20

Except for some extreme reactions and light isotopes . . .

e.g. hydrogen gas produced from water is strongly depleted in 2H and has a fractionation factor a2HH2O-H2 = 3.76 at 25C.

What will be the d2H value for H2 produced from water with d2HH2O = 75 at 25C?

d2HH2 = 754 VSMOW

(but using e, d2HH2 = 75 2760 = 2835)

So, use the e simplification . . . when a is close to 1when the d-values are not too different from the reference (i.e. within a few tens of permil of 0)

Fractionation and TemperaturelnaX-Y = aT2 + bT1 + c

Fractionation and Temperature

Fractionation - Other Systems

Equations

TCAA1ABC103lnaaReferenceTemperature Range

2Hwater-vapour15024.844-76.24852.612111.0112308249Majzoub (1971)

"252.40864.55-168761.0785109081Kakiuchi and Matsuo, 197910-40

1158.8-1620.1794.84-161.04109532460

water-ice019.31.019487449O'Neil (1968)0

"020.61.0208136445Arnason (1969)0

"020.61.0208136445Suzuoki and Kumura (1973)0

ice-vapour024.844-76.24873.21271.1354570411Majzoub (1971) plus Arnason (1969)

water vapour - hydrogen gas1000467.6-303.99492.5835948659Suess (1949)100-200

"2513389.61-204.3412493.4854851568Bottinga (1969) calculated0-600

water-hydrogen gas2513253.7620077025Bottinga (1969) plus Majzoub (1971)

methane-hydrogen gas 1100-8.949181.264-90.8887492.115560007Horibe and Craig (1975) written communication, in Friedman and O'Neil, 1977

"10025346-2238842.4199611894Bottinga (1969) calculated0-700

water vapour-methane256-60151-38201.0200799241Bottinga (1969a) calculated0-700

water vapour-methane25-7.696.188.4221.0226083089Bottinga (regressed)10-250

Water-methane25271.0272292017Bottinga (1969a) plus Majzoub (1971)0-100

water-H2S251290.498-127.98582.3576162845Galley et al. (1972)25-200

water-gypsum2502.1-22-150.9851544957Gonfiantini and Fontes (1967)

water-horneblend100023.9-7.91641.1779030038Suzuoki and Epstein (1976)450-850

water-biotite100021.32.81561.1685504761Suzuoki and Epstein (1976)450-850

18Owater-vapour251.137-0.4156-2.06679.31.0093728094Majzoub (1971)

"251.534-3.2062.6449.11.0091888065Bottinga and Craig (1969)

"255.9702-32.80152.2279.41.0094164749Kakiuchi and Matsuo, 197910-40

water-ice03.11.00310481O'Neil (1968)

"02.81.0028039237Suzuoki and Kumura (1973)

ice-vapour01.137-0.41561.014.71.0148591022Majzoub (1971) plus O'Neil (1968)

CO2-H2O25-0.020617.9942-19.9740.11.0409659662Bottinga (1968)0-100

Calcite-H2O152.780-2.8930.61.0310620421O'Neil, Clayton and Mayeda (1969)0-500

CO2-Calcite25-1.803410.611-2.779812.51.0126013566Bottinga, 19680-600

??Aragonite-H2O25

Dolomite-H2O503.20-1.529.11.029570614Northrop and Clayton, 1966200-800

Dolomite-Calcite1000.450-0.42.81.0028356482Sheppard and Schwarcz, 1970100-650

water-gypsum2502.3-3.74.01.0040220459Fontes (1965)

??SO4-H2O253.250-5.131.51.0319582212Lloyd (1968)0-500

??"252.880-4.128.31.028700314McKenzie and Truesdell (1977)

??"252.880-3.628.81.0292147928Mitzutani and Rafter (1969)110-200

anhydrite-H2O1003.880-2.925.01.0252780846Lloyd (1968)100-575

SiO2(amorph)-H2O503.520-4.35029.41.0297911547Kita et al., 198534-93

SiO2(quartz)-H2O501.91898.582-18.97726.01.0262938126Kawabe, 19780-100

SiO2(quartz)-H2O2003.550-2.57013.31.0133753418Shiro and Sakai, 1972195-573

Alkali feldspar-H2O5003.130-3.71.51.001537252Bottinga and Javoy, 1973500-800

Ca- feldspar-H2O5002.090-3.7-0.20.9997963114Bottinga and Javoy, 1973500-800

Kaolinite-H2O2002.50-2.878.31.00833119Land and Dutton, 1978

Smectite-H2O1502.670-4.8210.11.0101419219Yeh and Savin, 1977

Chlorite-H2O251.560-4.712.81.012930817Wenner and Taylor, 1971

13CCO2(g)-CO2(aq)2500.373-0.191.11.0010615692Vogel, Grootes and Mook, 1970

HCO3-CO2(g)2509.552-24.107.91.0079680679Mook, Bommerson and Staverman (1974)5-125

HCO3-CO2(aq)2509.866-24.129.01.0090099639Mook, Bommerson and Staverman (1974)5-125

CO3-HCO3250-0.8672.52-0.40.9996122405Mook, Bommerson and Staverman (1974)5-125

CO3-CO2(g)250.870-3.406.41.0064067805Deines et al. (1974)