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Oxygenation of the mid-Proterozoic atmosphere: clues from chromium isotopes in carbonates

G.J. Gilleaudeau1,2,

1Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen, Denmark
2Current address: School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA

R. Frei1,

1Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen, Denmark

A.J. Kaufman3,

3Department of Geology, University of Maryland, College Park, MD 20742, USA

L.C. Kah4,

4Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, USA

K. Azmy5,

5Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, Newfoundland A1B 3X5, Canada

J.K. Bartley6,

6Department of Geology, Gustavus Adolphus College, St. Peter, MN 56082, USA

P. Chernyavskiy7,

7Biostatistics/Radiation Epidemiology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD 20850, USA

A.H. Knoll8

8Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA

Affiliations  |  Corresponding Author  |  Cite as

Gilleaudeau, G.J., Frei, R., Kaufman, A.J., Kah, L.C., Azmy, K., Bartley, J.K., Chernyavskiy, P., Knoll, A.H. (2016) Oxygenation of the mid-Proterozoic atmosphere: clues from chromium isotopes in carbonates. Geochem. Persp. Let. 2, 178-187.

Geochemical Perspectives Letters v2, n2  |  doi: 10.7185/geochemlet.1618
Received 11 March 2016  |  Accepted 9 May 2016  |  Published 24 May 2016
Copyright © 2016 European Association of Geochemistry

Figure 1 (a) Cross-plot of raw Cr-isotope values and Al concentration in the leachate. Dashed line is at 400 ppm Al. (b) Cross-plot of raw Cr-isotope values and % detrital Cr based on enrichment above average shale. Dashed line is at 35 %.
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Figure 2 Compilation of all published Proterozoic Cr-isotope data including new data presented here. δ53Crauth values (after detrital correction) are presented for data from this study.
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Supplementary Figures and Tables

Figure S-1 Photomicrographs highlighting specific textural features in the (a,b) El Mreiti Group, (c,d,e) Turukhansk Uplift, and (f) Vazante Group. (a) Typical micritic limestone of the Touirist Formation. (b) Interval of fabric-destructive dolomitisation in the En Nesoar Formation. (c) Typical clotted micritic limestone of the Miroyedikha Formation. (d) Stylolitised and partially recrystallised intraclasts from the Miroyedikha Formation. (e) Coarse dolomitic spar filling inter-stromatolitic voids in the Miroyedikha Formation. (f) Fine-grained fabric-retentive dolomite (I) of the Lapa Formation (Vazante Group) surrounded by multiple stages (II, III, IV) of later dolomitic cements (>80 % by volume of the Lapa Formation consists of phase I dolomite).
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Figure S-2 Photomicrographs highlighting textural characteristics of the Angmaat Formation. A variety of primary depositional fabrics have been preserved through early dolomitisation, including evaporative features and tepee structures, a storm microbreccia, and microbial mats.
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Figure S-3 Geochemical indicators of diagenesis in all four sections. Circles are limestone and squares are dolostone. Bold points represent samples that were excluded from further discussion based on diagenetic criteria. Blue = Turukhansk, red = Angmaat, tan = El Mreiti, and green = Vazante.
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Figure S-4 Cross-plots of raw Cr-isotope values vs. other detrital indicators (Ti and Zr). Dashed lines represent 10 ppm Ti and 1 ppm Zr, which seem to be the cutoff values above which detrital Cr masks the authigenic Cr-isotope signal.
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Figure S-5 Cross-plot of raw Cr-isotope values and O-isotopes indicating that lower O-isotope values (potentially indicating diagenesis) correspond to unfractionated Cr-isotope values. This could mean that diagenetic alteration (at least in the case of the Vazante Group) has the potential to reset Cr-isotopes to crustal values.
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Table S-1 Sample information, mineralogy, Cr-isotope, and Al concentration data for carbonates from the Turukhansk Uplift, Vazante and El Mreiti groups, and the Angmaat Formation (~1.1 to 0.9 Ga).
SampleCore/OutcropFormationMineralogyCr (ppm)δ53Crraw (‰)Std. error (‰)% detrital Crδ53Crauth (‰)Al (ppm)Cr/Al x 1000
K95-22KAMSukh. Tung.LS0.21-0.220.0316.9-0.23336.5
K95-76STSukh. Tung.LS0.31-0.110.0321.5-0.11605.12
K95-86STSukh. Tung.LS0.210.080.06140.08277.87
K95-88-1STSukh. Tung.LS0.390.370.053.80.371329.21

KV 500 3CMM-500Ser. do P. Ver.DS1.180.550.0831.40.693373.5
KV 279 05CMM-279Mor. do Calc.DS4.421.
KV 279 12CMM-279Mor. do Calc.DS0.380.70.0933.40.911153.3
KV 279 11CMM-279Mor. do Calc.DS0.790.180.0847.7-3422.31
KV 279 01CMM-279Mor. do Calc.DS1.340.490.0713.70.511678.02
MAS 1006MASW 01LapaDS6.620.310.086.70.3140416.38
MAS 1002.5MASW 01LapaDS4.560.270.0815.40.286387.15
MAS 94MASW 01LapaDS4.920.
MAS 92MASW 01LapaDS0.540.680.0534.20.91683.21
MAS 86MASW 01LapaDS1.09-0.070.0659.6-5901.85
MAS 83MASW 01LapaDS0.98-0.050.0647.4-4222.32
MAS 82MASW 01LapaDS0.54-0.110.07100-10120.53
MAS 81MASW 01LapaDS0.66-0.150.0476.7-4601.44
MAS 73MASW 01LapaDS2.32-0.190.0816.5-0.193476.68
MAS 72MASW 01LapaDS2.77-0.170.0519.5-0.174915.64
MAS 70MASW 01LapaDS2.57-0.140.0512.9-0.143028.51
MAS 69MASW 01LapaDS5.6-0.230.0715.1-0.237707.28
MAS 60MASW 01LapaDS1.59-0.150.0867.2-9701.64
MAS 57MASW 01LapaDS0.87-0.110.0872.2-5711.52
MAS 52MASW 01LapaDS4.04-0.160.0635.6-0.1713063.09
MAS 46MASW 01LapaDS3.15-0.150.0624.6-0.157044.47
MAS 38MASW 01LapaDS1.08-0.080.06100-15990.68
MAS 22MASW 01LapaDS4.34-0.190.0627.4-0.210814.01
MAS 16MASW 01LapaDS0.87-0.120.06100-15310.57
MAS 13MASW 01LapaDS3.63-0.130.0515.2-0.135027.24
MAS 08MASW 01LapaDS0.8-0.210.0650.9-3702.16
MAS 07MASW 01LapaDS1.22-0.090.0630.1-0.083343.66
MAS 06MASW 01LapaDS1.20.050.0728.40.083103.87
MAS 04MASW 01LapaDS0.98-0.120.0625.3-0.122264.34
MAS 02MASW 01LapaDS0.89-0.130.0855.2-4471.99
KV 279 13CMM-279Mor. do Calc.DS0.720.60.0818.2-1196.04
MAS 87MASW 01LapaDS2.11-0.10.07100-29920.71
MAS 80MASW 01LapaDS1.09-0.110.0781.6-8081.35
MAS 79MASW 01LapaDS0.48-0.060.0973.5-3211.5
MAS 78MASW 01LapaDS1.26-0.210.0776.7-8781.43
MAS 77MASW 01LapaDS0.69-0.130.08100-12970.53
MAS 76MASW 01LapaDS1.36-0.040.0619.6-2425.63
MAS 74MASW 01LapaDS1.42-0.180.05100-17170.83
MAS 30MASW 01LapaDS2.23-0.120.0833.4-6773.29
MAS 12MASW 01LapaDS0.98-0.150.0778.7-7011.4
MAS 11MASW 01LapaDS0.96-0.040.0674.3-6481.48
MAS 10MASW 01LapaDS1.67-0.090.0845-6842.44
MAS 09MASW 01LapaDS1.48-0.120.0730.8-4153.57

F4-80F4Ag. el MabhaLS1.380.040.0985-10631.29
F4-87F4Ag. el MabhaLS1.8-0.130.0635.9-0.135883.06
F4-89F4Ag. el MabhaLS1.06-0.020.0488.2-8491.25
F4-90F4Ag. el MabhaLS0.80.030.0667.1-4901.64
F4-92F4Ag. el MabhaLS1.05-0.16089.6-8551.23
F4-95F4Ag. el MabhaLS1.16-0.050.0377-8091.43
F4-97F4Ag. el MabhaLS0.94-0.10.0573.5-6281.5
F4-19F4En NesoarLS2.
F4-21F4En NesoarDS11.050.680.034-40127.58


Turukhansk Uplift outcrop sections: KAM = Kammennaya-Bol’shaya Shorikha River; ST = Sukhaya Tunguska River; MIR = Miroyedikha River; YEN = Yenisei River
Angmaat Formation outcrop sections: AR = Alpha River; MI = Milne Inlet; TS = Tay Sound; WB = White Bay
LS = limestone
DS = dolostone
Standard error = standard deviation (s.d.) of isotopic values divided by the square root of n (number of runs)
% detrital Cr = derived from sample Cr/Al ratios using average shale composition as a proxy for detrital sediment (Cr = 90 ppm; Al = 8.89 wt. %)
δ53Crauth = Cr-isotopic composition of the authigenic seawater component corrected for the detrital component
RED = diagenetically-altered carbonate excluded from discussion on Cr-isotopes
BLUE = % detrital Cr > ~35 % so that δ53Crauth cannot be calculated

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Table S-2 δ13C, δ18O, major and trace element data, as well as sedimentary environments for the Turukhansk Uplift, Vazante and El Mreiti groups, and the Angmaat Formation (~1.1 to 0.9 Ga).
Sampleδ13C (‰)*δ18O (‰)*Sr (ppm)Mn (ppm)Mn/SrFe (ppm)Ti (ppm)Zr (ppm)Depositional environment
K95-9-0,1-9,63604811,33527610,040,31Near FWWB
K95-220,3-7,5545270,05276--Intertidal to shallow subtidal
K95-760,2-6,4598750,1310042,390,14Intertidal to shallow subtidal
K95-863,2-7,1937270,03852,730,44Intertidal to shallow subtidal
K95-88-11,2-7386640,16942,650,12Intertidal to shallow subtidal
K95-382,4-5,91451040,728782,760,2Open shelf above FWWB
K95-129-175--1712581,510113,070,4Below SWB
K95-140-34--1064123,943702,220,3Below SWB
K95-140-381,2-7,71257526,0473233,30,57Below SWB

835556,6619951,260,31Below SWB
K95-140-1552,3-7442365,3119883,250,49Below SWB
K95-140-1772-7,2884194,7872735,120,94Below SWB
K95-142-13-6,3502384,7939952,960,96Between FWWB and SWB
K95-142-15--481974,1319912,640,65Between FWWB and SWB
K95-142-203-6,4452184,8118512,880,36Between FWWB and SWB
K95-142-25--391774,5313781,920,75Between FWWB and SWB
K95-142-303-6,8431734,0817143,032,01Between FWWB and SWB
K95-142-602,9-6,5442836,4832183,840,53Between FWWB and SWB
K95-142-652,6-8,3322758,4727062,690,9Between FWWB and SWB
K95-140-481,7-7,437329888,5416490--Below SWB
K95-140-1260,7-10,21411214486,0320283--Below SWB

KV 500 3-0,7-6,9471122,410057,10,32Supratidal to intertidal
KV 279 051,6-4,561891,456377,60,39Supratidal to intertidal
KV 279 12--271033,76815--Supratidal to intertidal
KV 279 11-0,6-7,7524137,9217014,090,37Supratidal to intertidal
KV 279 012,2-7,7671632,4314962,960,19Supratidal to intertidal
MAS 1006--206231911,27236988,511,41Intertidal to shallow subtidal
MAS 1002.5--15914739,261683210,961,49Intertidal to shallow subtidal
MAS 94--160165210,35186498,760,89Intertidal to shallow subtidal
MAS 920,4-7,6643886,0658774,640,23Intertidal to shallow subtidal
MAS 86-3,4-8,936714654,014533412,380,81Intertidal to shallow subtidal
MAS 83-3,8-936713183,61373489,240,92Intertidal to shallow subtidal
MAS 82-2,4-8,524916896,825393917,91,35Intertidal to shallow subtidal
MAS 81-3,6-9,123215136,54258699,821,01Intertidal to shallow subtidal
MAS 73-0,3-5,8915676,24107108,920,52Intertidal to shallow subtidal
MAS 72-0,4-5,7864755,551021813,540,72Intertidal to shallow subtidal
MAS 700,7-6,2824775,8289629,280,5Intertidal to shallow subtidal
MAS 690,5-6,41114904,4193099,521,09Intertidal to shallow subtidal
MAS 600,7-7,4864294,981129110,721,93Intertidal to shallow subtidal
MAS 570-7,2806918,649886--Intertidal to shallow subtidal
MAS 52-0,3-8,820711495,574278755,871,53Intertidal to shallow subtidal
MAS 460-81395193,741826121,211,16Intertidal to shallow subtidal
MAS 38-0,8-9,720414216,983680144,421,53Intertidal to shallow subtidal
MAS 22-0,1-9,321614356,653233027,371,38Intertidal to shallow subtidal
MAS 160,3-8,522910704,682780212,872,16Intertidal to shallow subtidal
MAS 130-7,7954885,15107759,311,07Intertidal to shallow subtidal
MAS 08-1,9-9,823218748,112444610,411,45Intertidal to shallow subtidal
MAS 07-1,1-7,81534202,7569417,281,08Intertidal to shallow subtidal
MAS 060,5-7,11614002,49100565,080,75Intertidal to shallow subtidal
MAS 04-0,6-6,9824235,1499926,370,96Intertidal to shallow subtidal
MAS 02-0,8-7,61037086,86176167,672Intertidal to shallow subtidal
KV 279 133,2-12,3281023,7737--Supratidal to intertidal
MAS 87-8,2-9,44421224485,1380558--Intertidal to shallow subtidal
MAS 80-5,5-10,6306492816,16101215--Intertidal to shallow subtidal
MAS 79-2,1-8,7284432015,2891530--Intertidal to shallow subtidal
MAS 78-5,5-10,9223517023,2377272--Intertidal to shallow subtidal
MAS 77-2,9-9,2150279618,6342294--Intertidal to shallow subtidal
MAS 76-0,3-5,653138426,3511317--Intertidal to shallow subtidal
MAS 74-2,5-6,9116151813,131889--Intertidal to shallow subtidal
MAS 30-1-11,14136721,6412005--Intertidal to shallow subtidal
MAS 12-4,3-10,139017574,5351256--Intertidal to shallow subtidal
MAS 11-3,3-10,83568582,4338041--Intertidal to shallow subtidal
MAS 10-4,3-1147515103,249601--Intertidal to shallow subtidal
MAS 09-2,5-10,567029734,4958557--Intertidal to shallow subtidal

F4-480,8-7,52538073,1917993,180,32Epicratonic near FWWB
F4-80-5,1-944323605,33142197,970,48Epicratonic above FWWB
F4-87-5,2-8,646716133,45112602,540,5Epicratonic above FWWB
F4-89-4,5-7,540716704,194795,530,63Epicratonic above FWWB
F4-90-4,6-937616294,3493233,780,62Epicratonic above FWWB
F4-92-5,4-8,2218227410,4389306,340,7Epicratonic above FWWB
F4-95-4,6-10,116513728,3372655,730,59Epicratonic above FWWB
F4-97-4,2-81309817,5337175,730,64Epicratonic above FWWB
F4-99-3,7-7,3956947,299273,290,12Epicratonic near FWWB
F4-101-3,4-7,31064834,546673,410,22Epicratonic near FWWB
F4-105-2,7-6,71163513,0310283,310,13Epicratonic near FWWB
F4-107-2,7-7,51233362,7413102,60,28Epicratonic near FWWB
F4-109-2,3-7,3145435354533,70,41Epicratonic near FWWB
F4-111-2,2-7,31843091,6830323,670,5Epicratonic near FWWB
F4-113-2-7,73092900,9418873,710,3Epicratonic near FWWB
F4-115-1,1-71551631,057323,520,1Epicratonic near FWWB
F4-19-2,3-5,797149915,536024--Epicratonic intertidal to shallow subtidal
F4-21-2,9-4,297249825,8126646--Epicratonic intertidal to shallow subtidal

MI-27390--351093,091065,450,07Shallow subtidal ooid shoal
MI-27450--381102,91325,650,03Shallow subtidal ooid shoal
MI-3420--37772,1904,30,05Shallow subtidal ooid shoal
TY-13--532234,213514,590,08Supratidal to intertidal
TY-18025B3,1-3,5522805,394605,280,06Supratidal to intertidal
TP-24260--41721,741957,010,28Supratidal to intertidal
TY-3975--593115,244944,960,03Supratidal to intertidal
TY-4--541963,612759,990,25Supratidal to intertidal
WB-13284A--653154,815823,920,11Intertidal to shallow subtidal
WB-3600--652754,213336,840,05Intertidal to shallow subtidal
WB-815--631071,712947,190,37Intertidal to shallow subtidal
WB2-7955--351253,562294,290,06Intertidal to shallow subtidal
WB2-87651,7-2,7681832,727780,08Intertidal to shallow subtidal
WB94-122,6-2,5412997,235205,650,08Intertidal to shallow subtidal
WB94-142,7-0,7443648,25976,220,1Intertidal to shallow subtidal
WB94-33,3-2,458971,662315,810,04Intertidal to shallow subtidal
WB94-63-4462405,194703,750,03Intertidal to shallow subtidal
WB94-162,9-2,86870210,3314838,480,11Intertidal to shallow subtidal

13C and δ18O data previously published for the Turukhansk Uplift (Bartley et al., 2001 Bartley, J.K., Semikhatov, M.A., Kaufman, A.J., Knoll, A.H., Pope, M.C., Jacobsen, S.B. (2001) Global events across the Mesoproterozoic-Neoproterozoic boundary: C and Sr isotopic evidence from Siberia. Precambrian Research 111, 165-202. ), Vazante Group (Azmy et al., 2001 Azmy, K., Veizer, J., Misi, A., de Oliveira, T.F., Sanches, A.L., Dardenne, M.A. (2001) Dolomitization and isotope stratigraphy of the Vazante Formation, São Francisco Basin, Brazil. Precambrian Research 112, 303-329. ), El Mreiti Group (Gilleaudeau and Kah, 2013a Gilleaudeau, G.J., Kah, L.C. (2013a) Carbon isotope records in a Mesoproterozoic epicratonic sea: carbon cycling in a low-oxygen world. Precambrian Research 228, 85-101. ), and Angmaat Formation (Kah et al., 1999 Kah, L.C., Sherman, A.B., Narbonne, G.M., Kaufman, A.J., Knoll, A.H. (1999) d13C stratigraphy of the Proterozoic Bylot Supergroup, northern Baffin Island: implications for regional lithostratigraphic correlations. Canadian Journal of Earth Sciences 36, 313-332. ).
FWWB = fair weather wave base; SWB = storm wave base
RED = diagenetically-altered carbonate excluded from discussion on Cr-isotopes
BLUE = % detrital Cr >~35 % so that δ53Crauth cannot be calculated

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