New Record of the Carbon Cycle From Early Triassic Arabia

A new high-resolution δ13C record for the Early Triassic: Insights from the Arabian Platform

Authors:

1. M.O. Clarkson (a)
2. S. Richoz (b)
3. R.A. Wood (a)
4. F. Maurer (c)
5. L. Krystyn (d)
6. D.J. McGurty (a)
7. D. Astratti (e)

Affiliations:

a. The Grant Institute, School of Geosciences, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JW, UK

b. Commission for the Palaeontological and Stratigraphical Research of Austria, Austrian Academy of Sciences c/o Institute of Earth Sciences, University of Graz, Heinrichstraße 26, 8010 Graz, Austria

c. Maersk Oil, Esplanaden 50, 1263 Copenhagen K, Denmark

d. Institute for Paleontology, Vienna University, Althanstrasse 14, 1090 Vienna, Austria

e. Schlumberger Stavanger Research Center, Risabergveien 3, P.O. Box 8013, N-4068 Stavanger, Norway

Abstract:

A new carbon isotope record with conodont biostratigraphy is presented for the entire Early Triassic from the Musandam Peninsula, United Arab Emirates (UAE). This is a near-continuous and exclusively shallow marine carbonate succession that allows analysis of a high-resolution primary carbon cycling signature in the absence of significant depth-dependent or lithologic controls. The Musandam carbon isotope record can be broadly correlated with global isotopic events but also resolves additional features, including the presence of significant negative events during the previously identified positive excursions at both the Dienerian/Smithian and Smithian/Spathian boundaries. A further positive event is revealed during the development of the mid-Spathian negative excursion, a feature not previously reported in any other section. These new short-lived events are probably related to the occurrence of the more widely recognized Early Triassic excursions, and may represent fluctuations in the driving mechanisms superimposed on the continued instability of the global carbon cycle in the aftermath of the end-Permian extinction. Together, these features highlight additional complexities to the Early Triassic carbon cycle perturbations than previously documented.