Abstract
A limited (Re‑check) weathering study was conducted to evaluate whether existing weathering data for Kobbe crude oil from the Goliat field are applicable to Zagato crude oil. The study compared artificial weathering of Zagato to a 250°C+ residue and relevant oil weathering properties of the fresh oil and residue. The results show that Zagato and Kobbe are highly comparable. Both are classified as light crude oils with closely matching GC‑FID fingerprints, physico‑chemical properties, and emulsification behaviour after weathering. Minor differences observed are considered to fall within experimental uncertainty.
Based on these findings, the existing Kobbe weathering data are considered representative for Zagato crude oil and are recommended for use in oil spill response and environmental risk assessments, without the need for a full standardized