Archean ocean

Habicht KS, Canfield DE (1997) Sulfur isotope fractionation during bacterial sulfate reduction in organic-rich sediments. Geochim CosmochimActa61(24) 5351-5361 Habicht KS, Gade M, Thamdrup B, Berg P, Canfield DE (2002) Calibration of sulfate levels in the Archean ocean. Science 298 2372-2374... 

Yamaguchi KE, Beard BL, Johnson CM, Ohkouchi N, Ohmoto H (2003) Iron isotope evidence for redox stratification of the Archean oceans. Geochim Cosmochim Acta 67 550... 

Links between Earth Degassing, Gold and the Redox State of Late Archean Oceans... 

Walshe, J.L. Kendrick, M.A. 2009. Links between planetary degassing, gold and the redox state of Late Archean Oceans 19 V.M. Goldschmidt Conference - Challenges to Our Volatile Planet, 2009. 

Jacob D., Jagoutz E., Lowry D., Mattey D., and Kudrjavtseva G. (1994) Diamondiferous eclogites from Siberia remnants of Archean oceanic crust. Geochim. Cosmochim. Acta 58, 5191-5207. 

Jacob D. E. and Foley S. F. (1999) Evidence for Archean ocean crust with low high field strength element signature from diamondiferous eclogite xenoliths. Lithos 48, 317-336. 

Desrochers J. P., Hubert C., Ludden J. N., and Pilote P. (1993) Accretion of Archean Oceanic Plateau fragments in the Abitibi Greenstone Belt, Canada. Geology 21, 451-454. 

At present, little can be said with any degree of confidence about the composition of the proposed Hadean ocean, but it was probably not very different from that of the Early Archean ocean, about which a good deal can be inferred. 

The data for the mineralogy of BIFs teU much the same story. These sediments provide strong evidence for the view that the deep oceans were anoxic throughout Archean time (James, 1992). Evidence regarding the oxidation state of the shallow parts of the Archean oceans is still very fragmentary. The shallow water facies of the 2.49 0.03 Griquatown iron formation (Nelson et al., 1999) in the Transvaal Supergroup of South Africa (Beukes, 1978, 1983 Beukes and Klein, 1990) were deposited on the —800 km X 800 km... 

Franqois L. M. (1987) Reducing power of ferrous iron in the Archean ocean 2. Role of Fe(OH) photo-oxidation. Paleoceanography 2, 395-408. 

Habicht K. S., Gade M., Thamdrup B., Berg P., and Canfield D. E. (2002) Cahbration of sulfate levels in Archean ocean. Science 298, 2372-2374. 

Ohmoto H. (1992) Biogeochemistry of sulfur and the mechanisms of sulfide-sulfate minerahzation in Archean oceans. In Early Organic Evolution Implications for Mineral and Energy Resources (eds. M. Schidlowdd, S. Golubic, M. M. Kimberly, and P. A. Trudinger). Springer, Berlin. 

Sulfur isotope studies have also provided insights into the transition from Archean low Po to higher values in the Proterozoic. In the same studies that revealed extremely low Archean ocean sulfate concentrations, it was found that by —2.2 Ga, isotopic compositions of sedimentary sulfates and sulfides indicate bacterial sulfate reduction under more elevated seawater sulfate concentrations compared with the sulfate-poor Archean (Habicht et al., 2002 Canfield et al., 2000). As described above, nitrogen isotope ratios in sedimentary kerogens show a large and permanent shift at —2.0 Ga, consistent with denitrification, significant seawater nitrate concentrations, and thus available atmospheric O2. 

Hoffman, P. F. Ranalli, G. 1988. Archean oceanic flake tectonics. Geophysical Research Letters, 15, 1077-1080. 

Kusky, T. M. 1990. Evidence for Archean ocean opening and closing in the southern Slave Province. Tectonics, 9, 1533-1563. 

Kusky, T. M. Kidd, W. S. F. 1992. Remnants of an Archean oceanic plateau, Belingwe greenstone belt, Zimbabwe. Geology, 20, 43-46. 

The high extent of hydrothermal Zn delivery to the surface of Earth during the earliest stages of its history is reflected in the association of present day major zinc ore deposits (built of ZnS) with Archean oceanic spreading centres and island arc terrains [260,261]. 

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