1. Japan Oil, Gas and Metals National Corporation, 1-2-2 Hamada, Mihama-ku, Chiba-shi, Chiba 261-0025, Japan
2. The National Energy Technology Laboratory, 626 Cochrans Mill Road, Pittsburgh, Pennsylvania 15236, United States
3. The U.S. Geological Survey, Box 25046, Denver, Colorado 80255, United States
4. Geological Survey of Canada, Natural Resources Canada, Central Division 601 Booth Street, Ottawa, Ontario K1A 0G1, Canada
5. Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, P.R. China