Upper Cretaceous carbon- and oxygen-isotope stratigraphy of hemipelagic carbonate facies from southern Tibet, China

From: Journal of the Geological Society | Date: March 1, 2006| Author: | Copyright information

Abstract:

A high-resolution carbon-isotope curve derived from Upper Cretaceous hemipelagic sediments cropping out at Tingri, southern Tibet, shows similarities to patterns established on other continents, notably in the presence of a well-defined positive excursion across the Cenomanian-Turonian boundary where δ^sup 13^C values exceed 3.5[per thousand]. From the upper Turanian to the lower Campanian, δ^sup 13^C values generally decline, apart from a minor positive excursion in the middle Coniacian: a trend that departs from that recorded from Europe. Relatively low δ^sup 13^C ...

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