THE IMPORTANCE OF SAMPLING DEPTH AND SPATIAL VARIABILITY ON TERRESTRIAL δ13CORG VALUES ACROSS THE K-PG BOUNDARY
To test the effects of modern contamination and lithological control, we collected samples from a traditional hand trench, a coring device, and a deep (>1m) trench dug using a backhoe. Samples obtained using each method are collected across the same stratigraphic interval within 20 m (geographically) of each other, so their relative reliability can be assessed. Results show that core samples values are more negative, but the general trends, including the negative K-Pg excursion, are preserved in all sampling methods. There does not appear to be a significant lithological bias to δ13Corg values. Additionally, samples were also collected from hand trenches over a greater, but still fairly small (<10 km2) area to compare the effects of local spatial variability in δ13Corg signals. Results of these samples will be presented at the conference.