Heavy carbon in two-billion-year-old marbles from Lofoten-Vesteralen, Norway: Implications for the Precambrian carbon cycle

Journal Article · Mon May 01 04:00:00 EDT 1989 · Geochimica et Cosmochimica Acta; (USA)

DOI:https://doi.org/10.1016/0016-7037(89)90216-0· OSTI ID:5022894

Baker, A J ^[1]; Fallick, A E ^[2]

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1. Grant Institute of Geology, Edinburgh (Scotland) Scottish Universities Reactor Research Centre, Glasgow (Scotland)
2. Scottish Universities Reactor Research Centre, Glasgow (Scotland)

High {delta}{sup 13}C values of up to 12{per thousand} (PDB) occur in two-billion-year-old high-grade marbles from Lofoten-Vesteralen, Norway. Correlations of high {delta}{sup 13}C with high {delta}{sup 18}O of up to 25{per thousand} (SMOW) suggest that premetamorphic {delta}{sup 13}C values were above 10{per thousand} (PDB) over a broad area. These marbles are associated with graphite rich schists, often containing in excess of 25 wt% carbon and having {delta}{sup 13}C {approximately} {minus}25{per thousand} (PDB). A compilation of data in the literature suggests that the deposition of limestones with isotopically heavy carbon was common at around 2.0 Ga. The data are consistent with worldwide or localized positive excursions in the {delta}{sup 13}C of marine bicarbonate. Positive excursions in {delta}{sup 13}C of seawater at this time may have coincided with a transition to a more oxidizing atmosphere and ocean.

• OSTI ID: 5022894
• Journal Information: Geochimica et Cosmochimica Acta; (USA), Journal Name: Geochimica et Cosmochimica Acta; (USA) Vol. 53:5; ISSN GCACA; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
CARBON 13
CARBON CYCLE
CARBON ISOTOPES
CHEMICAL COMPOSITION
CHEMISTRY
CORRELATIONS
EUROPE
EVEN-ODD NUCLEI
GEOCHEMISTRY
GEOLOGIC AGES
ISOTOPE RATIO
ISOTOPES
LIGHT NUCLEI
MARBLE
METAMORPHIC ROCKS
METAMORPHISM
NORWAY
NUCLEI
PETROGENESIS
PRECAMBRIAN ERA
ROCKS
SCANDINAVIA
STABLE ISOTOPES
WESTERN EUROPE