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

3.3 Palaeotectonic and Palaeogeographic Evolution of Fennoscandia in the Early Palaeoproterozoic

“…13 C values (Baker and Fallick 1989), which provide a chemostratigraphic correlation to the isotopically similar carbonates on the Karelian craton recording the Lomagundi-Jatuli positive excursion of carbonate carbon (e.g. Karhu 1993;Melezhik et al 1999a).…”

Carbon isotopes of Mesoproterozoic–Neoproterozoic sequences from Southern São Francisco craton and Araçuaí Belt, Brazil: Paleographic implications

“…These fluctuations represent global features in the sedimentary records that may be used as stratigraphic markers (Knoll et al, 1986;Magaritz et al, 1986;Baker and Fallick, 1989;Iyer et al, 1995;Kaufman and Knoll, 1995;Buick et al, 1998;Melezhik et al, 1999;Santos et al, 2000;Lindsay and Brassier, 2002). Carbonate carbon isotopic profiles from other sections of the Bambuí Group (Fig.…”

“…While positive carbon isotope excursions have been described in Paleoproterozoic (Knoll et al, 1986;Baker and Fallick, 1989;Buick et al, 1998;Melezhik et al, 1999;Lindsay and Brassier, 2002) and Neoproterozoic (Iyer et al, 1995;Kaufman and Knoll, 1995;Magaritz et al, 1986;Santos et al, 2000) carbonate sequences worldwide, Mesoproterozoic carbonate sequences usually have d 13 C PDB values similar to Phanerozoic sequences (Veizer et al, 1980;Buick et al, 1995;Kha et al, 1999). In most instances, these carbon isotope variations have been attributed to global processes, such as glaciation events or other mechanisms that disturb the inorganic and organic carbon reservoirs.…”

Variations of Stable Isotope Ratios in Nature

“…Especially noteworthy are very high δ 13 C-values of up to 10 ‰ and higher for 2.2-2.0 Ga old carbonates and at the end of the Proterozoic with both periods representing periods of increased burial of organic carbon (Knoll et al 1986, Baker andFallick 1989;Derry et al 1992 and others). By compiling the data base for the Proterozoic, Shields and Veizer (2002) (Fig.…”