Do stable carbon isotopes of brown coal woods record changes in Lower Miocene palaeoecology?

Abstract

Stable carbon isotope ratios of fossil wood from the Miocene brown coal deposits in former East Germany are compared with palaeobotanical and sedimentological data to test the use of stable isotopes in determining palaeoenvironment. Significant differences in the chemical composition of samples from different horizons were observed. Those specimens preserved under the most (bio)degrading conditions yielded stable carbon isotope values least representative of original wood specimens. Overall, the chemical preservation of the wood was seen to affect the stable isotope signal but deconvolving the preservational bias using a molecular approach enabled estimations of d13Cbiomass and d13Cpalaeoatmosphere that were then used to interpret more fully the palaeoenvironment.