[presented by] U.S. Geological Survey in collaboration with the National Park Service ; producer-director, Anne Tubiolo ; writers, Sandra Clark, Anne Tubiolo, Elizabeth Romanaux
a production of U.S. Department of the Interior, U.S. Geological Survey ; produced, directed & edited by Steve Wessells ; written by Donna Matrazzo, Steve Wessells
a production of the U.S. Geological Survey, U.S. Department of the Interior ; written and directed by Jonathan Swinchatt ; produced by Steve Brantley, Jonathan Swinchatt