1. Department of Geological and Mining Engineering and Sciences; Michigan Technological University; Houghton Michigan USA
2. Department of Geology and Geophysics; Novosibirsk State University; Novosibirsk Russia
3. Trofimuk Institute of Petroleum Geology and Geophysics; Siberian Branch of Russian Academy of Science; Novosibirsk Russia
4. Department of Physics; Michigan Technological University; Houghton Michigan USA