FILE PHOTO: The Tengizchevroil (TCO) oil and gas refinery plant at Tengiz oil field in western Kazakhstan is seen in this August 24, 2004 file photograph. REUTERS/Shamil Zhumatov/File Photo
FILE PHOTO: The Tengizchevroil (TCO) oil and gas refinery plant at Tengiz oil field in western Kazakhstan is seen in this August 24, 2004 file photograph. REUTERS/Shamil Zhumatov/File Photo