Carbon isotope geochemistry of the Frasnian-Famennian transition

Buggisch W, Joachimski M, Ostertag-Henning C, Pancost R, Freeman K (2002)

Publication Type: Journal article, Original article

Publication year: 2002

Journal

Palaeogeography, Palaeoclimatology, Palaeoecology Elsevier

Publisher: Elsevier

Book Volume: 181

Pages Range: 91-109

DOI: 10.1016/S0031-0182(01)00474-6

Abstract

Carbon isotope records for inorganic and total organic carbon (TOC) as well as for individual organic biomarkers show two positive excursions in the Late Frasnian with comparable shape and amplitude in δ¹³C. The positive shifts in δ¹³C can be correlated with the deposition of the Kellwasser horizons. The inorganic carbon isotope excursions are explained by an enhanced organic carbon burial that is expected to lower the concentration of oceanic dissolved CO2. TOC δ¹³C values do not exhibit a larger shift than that recorded by inorganic carbon δ¹³C values; this is unexpected since a decrease in the dissolved CO2 concentration should result in lower carbon isotope fractionation during photosynthesis (εp). δ¹³C values of presumed algal biomarkers (low-molecular-weight n-alkanes, pristane, phytane), although offset by ∼2.5‰, exhibit essentially identical records as TOC, and confirm this unexpected result. It is proposed that high atmospheric and oceanic CO2 concentrations during the Devonian resulted in maximum photosynthetic fractionation. Any change in the CO2 concentration would thus not affect εp. As such, δ¹³C of primary organic carbon and δ¹³Ccarb will exhibit parallel excursions. The data imply that carbon isotopes and the relationship between εp and [CO2] will not be effective to study changes in pCO2 levels during the Devonian since CO2 concentrations were too high. © 2002 Elsevier Science B.V. All rights reserved.

Authors with CRIS profile

Werner Buggisch Naturwissenschaftliche Fakultät Michael Joachimski Lehrstuhl für Geologie (Exogene Dynamik)

How to cite

APA:

Buggisch, W., Joachimski, M., Ostertag-Henning, C., Pancost, R., & Freeman, K. (2002). Carbon isotope geochemistry of the Frasnian-Famennian transition. Palaeogeography, Palaeoclimatology, Palaeoecology, 181, 91-109. https://doi.org/10.1016/S0031-0182(01)00474-6

MLA:

Buggisch, Werner, et al. "Carbon isotope geochemistry of the Frasnian-Famennian transition." Palaeogeography, Palaeoclimatology, Palaeoecology 181 (2002): 91-109.

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