FILE - In this Sept. 2, 1998 file photo, a couple enjoy lunch on one of the scenic points at Grand Canyon West on the Hualapai Indian reservation in Arizona. A new study published in the journal Science Thursday, Nov. 29, 2012, suggests the western Grand Canyon formed 70 million years ago. Some scientists disagree and believe the canyon was mainly carved by the Colorado River in the past 5 to 6 million years. (AP Photo/Jeff Robbins, File)