1. Department of Earth Sciences University of Oxford South Parks Road Oxford OX1 3AN UK
2. Department of Earth Science and Engineering Imperial College London Prince Consort Road London SW7 2BP UK
3. Shell International Limited 40 Bank St, Canary Wharf London E14 5NR UK
4. Petrotechnical Data Systems B.V. Lange Kleiweg 10 2288 GK Rijswijk The Netherlands