Ellen J. Prager writes on geology and marine-related topics for children and adults, and is the assistant dean at the Rosenstiel School of Marine and Atmospheric Science at the University of Miami. She's the author of The Furious Earth: The Science and Nature of Earthquakes, Volcanoes, and Tsunamis, as well as several of National Geographic’s Jump into Science books.

Nancy Woodman is a children’s book author and illustrator. She has worked on Sea-Fari Deep and the Jump into Science books Dirt, Volcano!, and Sand, a Parents' Choice winner for 2001. Woodman is also the cocreator of Worm Vue Wonders, an educational product about the role of earthworms in soil. She lives in Poulsbo, Washington. To learn more, visit nanneroo.com.