Isotopic analysis performed at the Geology Department of UNamur

Carbon isotope (δ¹³C) variations are used for global correlations of geological sections in which we discover fossils. Isotopic analyses on organic matter require rigorous laboratory preparation for each sample. Each drilled sample is carefully examined to avoid potential contamination, before grinding process. Powders are treated with a 25% hydrochloric acid solution in order to suppress any carbonates (-CO₃) content in the rock sample. Afterwards, neutralization of the sediment (pH ≈ 7) is reached by successive distilled water addition and centrifugation processes. Total Organic Carbon content (TOC, %) and Sulfur (S, %) content are measured with a standard carbon analyser LECO. Isotopic analyses are performed on a mass spectrometer. Organic carbon isotopic values are normalized to the international PDB standard (δ¹³C_org).