About the Author

Allen F. Glazner is the Kenan Distinguished Professor of Geological Sciences at the University of North Carolina at Chapel Hill. A native Californian, he holds a PhD from the University of California at Los Angeles and has done research in the Sierra Nevada and Mojave Desert from his undergraduate days at Pomona College. Greg M. Stock was born and raised in the Sierra Nevada just north of Yosemite. He has a bachelor�s degree in geology from Humboldt State University and a PhD in earth science from the University of California at Santa Cruz. Greg is Yosemite National Park�s first-ever park geologist.