EXPLORING THE ROLE OF MID-CRETACEOUS CARBON CYCLING ON FLOWERING PLANT RADIATION: AN INTEGRATED APPROACH FROM THE NON-MARINE SEDIMENTS OF WEST GREENLAND
We aim to generate high-resolution pCO2 records spanning mid-Cretaceous OAEs using the stomatal density method on fossil leaf cuticle from non-marine sediments of the Nuussuaq Peninsula, West Greenland. These fluvio-deltaic and lacustrine deposits have been known to contain well-preserved fossil flora since the collections of Oswald Heer (1870’s), and extensive work by Austin Boyd formed the basis of our field strategy. Carbon-isotope stratigraphy, generated from fossil wood and bulk organic matter, provides a refined age definition of the sediments exposed along the north coast of the peninsular. In agreement with previous palynological estimates, our data indicate the exposed Kome Formation is no older than earliest Albian, and a positive carbon-isotope excursion within the formation is probably correlative to OAE1b. The combination of macrofossil floral assemblages and our carbon-isotope stratigraphy suggests the Ravn Kløft Member of the Atane Formation likely spans the Albian–Cenomanian boundary (OAE1d). We provide the stomatal investigation results with respect to pCO2 and demonstrate the excellent fossil preservation to reconstruct other aspects of terrestrial palaeoenvironments.