Evidence of Paleoclimate Change in Early Triassic Iran

87Sr/86Sr stratigraphy from the Early Triassic of Zal, Iran: Linking temperature to weathering rates and the tempo of ecosystem recovery

Authors:

Sedlack et al

Abstract:

Recovery from the Late Permian mass extinction was slowed by continued environmental perturbations during the Early Triassic. Rapid fluctuations of the Early Triassic marine carbonate carbon isotope record indicate instability in the global carbon cycle, and recent δ18Oapatite studies link elevated temperatures to the prolonged biotic recovery. High temperatures potentially caused enhanced continental weathering that was detrimental to marine ecosystems, but linking weathering rates to temperature has proven difficult. One proxy for weathering is the 87Sr/86Sr of marine carbonate; we present here an 87Sr/86Sr record from an upper Permian–lower Triassic succession near Zal, Iran, that is coupled to a δ13Ccarbonate record. An increase in the rate of 87Sr/86Sr rise from the Dienerian to the Smithian may be linked to elevated continental weathering rates caused by warming during the Smithian.