NGU has performed geophysical logging in two deep boreholes at the Fen complex at Ulefoss, Vestfold and Telemark county. The boreholes were 1000 and 716 m, deep drilled in the carbonate volcano. The purpose was to get petrophysical data for this very unusual carbonatite volcanic rock and to see if there are any orrelation between REE content and petrophysical data. Temperature data was also of interest.
