1. Department of Geologic and Planetary Sciences, Caltech Institute of Technology, Pasadena CA 91125, USA
2. Lundin Norway AS, Lysaker 1366, Norway
3. Aker BP ASA, Lysaker 1366, Norway
4. Geological Survey of Norway, Trondheim 7491, Norway
5. Department of Geology, University of Tartu, Tartu 50411, Estonia