Is mid-late Paleozoic ocean-water chemistry coupled with epeiric seawater isotope records?

Isotopes of epeiric sea carbonates are used to construct seawater records for modeling global changes in Paleozoic ocean chemistry, climate, and for intercontinental correlation. We present for the first time geochemical results of Paleozoic brachiopods (biogenic low-Mg calcite, bLMC) from open-ocean Permian–Carboniferous seamounts of Japan situated in the tropical mid-Panthalassic Ocean. Strontium isotope values of bLMC from the Panthalassic and Paleotethys Oceans are coupled with those of coeval specimens from epeiric seas of North America, Europe, and Russia ( p = 0.393), but not with those of epeiric sea whole rocks (matrix aragonite/calcite, mAC; p = 0.029) and conodonts (biogenic apatite, bA; p = 0.031). Oxygen isotope values of bLMC from the Panthalassic and Paleotethys exhibit mixed results with studies of counterparts from epeiric seas ( p = 0.596) reflecting overprinting of local environmental conditions on global trends. Carbon isotope values of bLMC and mAC from the Panthalassic and Paleotethys Oceans are generally dissimilar to those of coeval material from epeiric seas of North America, Europe, and Russia ( p = 0.001 and 0.002, respectively). Factors such as water mass stratification, evaporation, dilution, depth, temperature, carbon burial and/or oxidation variations, and syndepositional diagenesis within the local environment probably influenced the chemistry of the fauna and accumulating sediments. This decoupling of carbon and oxygen isotope values from the open ocean with those from epeiric seas makes questionable the use of isotope results from epeiric seas for international correlation, constructing global seawater records, determining fluxes in the global carbon cycle, and for modeling climate changes and subsequently atmospheric carbon dioxide levels.

[1]  B. Beauchamp,et al.  Intrabasin variability of the carbon-isotope record across the Permian–Triassic transition, Sverdrup Basin, Arctic Canada , 2008 .

[2]  Y. Isozaki,et al.  The Paleozoic minimum of 87Sr/86Sr ratio in the Capitanian (Permian) mid-oceanic carbonates: A critical turning point in the Late Paleozoic , 2008 .

[3]  L. M. Walter,et al.  Controls on the δ13C of dissolved inorganic carbon in marine pore waters: An integrated case study of isotope exchange during syndepositional recrystallization of biogenic carbonate sediments (South Florida Platform, USA) , 2007 .

[4]  S. Hesselbo,et al.  Atypical diagenetic effects on strontium-isotope composition of Early Jurassic belemnites, Queen Charlotte Islands, British Columbia, Canada , 2007 .

[5]  Hodaka Kawahata,et al.  A unique carbon isotope record across the Guadalupian¿Lopingian (Middle¿Upper Permian) boundary in mid-oceanic paleo-atoll carbonates: The high-productivity ¿Kamura event¿ and its collapse in Panthalassa , 2007 .

[6]  M. Joachimski,et al.  Carbon, oxygen and strontium isotope records of Devonian brachiopod shell calcite , 2006 .

[7]  C. Korte,et al.  87Sr/86Sr record of Permian seawater , 2006 .

[8]  H. Sano.  Impact of long-term climate change and sea-level fluctuation on Mississippian to Permian mid-oceanic atoll sedimentation (Akiyoshi Limestone Group, Japan) , 2006 .

[9]  C. Holmden,et al.  Local Controls on Carbon Cycling in the Ordovician Midcontinent Region of North America, with Implications for Carbon Isotope Secular Curves , 2006 .

[10]  C. Korte,et al.  δ18O and δ13C of Permian brachiopods: A record of seawater evolution and continental glaciation , 2005 .

[11]  M. Saltzman.  Phosphorus, nitrogen, and the redox evolution of the Paleozoic oceans , 2005 .

[12]  Matthew R. Saltzmana,et al.  Carbon cycle models based on extreme changes in y 13 C : an example from the lower Mississippian , 2004 .

[13]  J. Banner.  Radiogenic isotopes: systematics and applications to earth surface processes and chemical stratigraphy , 2004 .

[14]  U. Brand.  Carbon, oxygen and strontium isotopes in Paleozoic carbonate components: an evaluation of original seawater-chemistry proxies , 2004 .

[15]  A. Immenhauser,et al.  An alternative model for positive shifts in shallow‐marine carbonate δ13C and δ18O , 2003 .

[16]  A. Logan,et al.  Geochemistry of modern brachiopods: applications and implications for oceanography and paleoceanography , 2003 .

[17]  E. Grossman,et al.  Isotopic records of brachiopod shells from the Russian Platform — evidence for the onset of mid-Carboniferous glaciation , 2001 .

[18]  T. Nakazawa.  Carboniferous reef succession of the Panthalassan open-ocean setting: example from Omi Limestone, central Japan , 2001 .

[19]  X. Lee,et al.  No vital effect on δ18O and δ13C values of fossil brachiopod shells, Middle Devonian of China , 2000 .

[20]  H. Strauss,et al.  87Sr/86Sr, δ13C and δ18O evolution of Phanerozoic seawater , 1999 .

[21]  E. Grossman,et al.  Carboniferous isotope stratigraphies of North America: Implications for Carboniferous paleoceanography and Mississippian glaciation , 1999 .

[22]  J. Tazawa.  Pre-Neogene tectonic divisions and Middle Permian brachiopod faunal provinces of Japan , 1998 .

[23]  R. E. Denison,et al.  CONSTRUCTION OF THE SILURIAN AND DEVONIAN SEAWATER 87SR/86SR CURVE , 1997 .

[24]  C. Holmden,et al.  Isotopic evidence for geochemical decoupling between ancient epeiric seas and bordering oceans: Implications for secular curves , 1997 .

[25]  E. Martin,et al.  Sr and Nd isotopes at the prmian/triassic boundary: A record of climate change , 1995 .

[26]  L. M. Walter,et al.  Depletion of 13C in seawater ΣC02 on modern carbonate platforms: Significance for the carbon isotopic record of carbonates , 1994 .

[27]  J. Banner,et al.  The isotopic record of ocean chemistry and diagenesis preserved in non-luminescent brachiopods from Mississippian carbonate rocks, Illinois and Missouri , 1994 .

[28]  D. Bowman.  Discussion of Pimm et al., 1994 (Bird Extinctions in the Central Pacific [and Discussion]) , 1994 .

[29]  R. E. Denison,et al.  Construction of the Mississippian, Pennsylvanian and Permian seawater 87Sr86Sr curve , 1994 .

[30]  R. Berner,et al.  GEOCARB III : A REVISED MODEL OF ATMOSPHERIC CO 2 OVER PHANEROZOIC TIME , 2001 .

[31]  L. M. Walter,et al.  Dissolution and recrystallization in modern shelf carbonates: evidence from pore water and solid phase chemistry , 1993, Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences.

[32]  Yoji Kobayashi,et al.  Strontium isotope profile of Carboniferous-Permian Akiyoshi Limestone in southwest Japan , 1991 .

[33]  H. Sano,et al.  Paleogeographic reconstruction of accreted oceanic rocks, Akiyoshi, southwest Japan , 1988 .

[34]  H. Elderfield.  Strontium isotope stratigraphy , 1986 .