Allan Ludman is a Professor in the Department of Earth and Environmental Sciences at Queens College of the City University of New York. He has devoted more than four decades to deciphering the evolution of the northern Appalachians through field and laboratory studies of rocks and structures in Maine and New Brunswick. Allan has taught Introductory Geology and has supervised the associated laboratory sections for over 35 years. He is also the Director of GLOBE NY Metro, a K-12 science teacher development program in the New York City area, dedicated to promoting hands-on, inquiry-based Earth Systems educational methods and materials for K-12 teachers. In addition to research papers and Laboratory Manual for Introductory Geology , Allan co-authored Physical Geology . Stephen Marshak is a Professor Emeritus of Geology at the University of Illinois, Urbana-Champaign, where he taught for 35 years. During this time, he also served as Head of the Department of Geology and as Director of the School of Earth, Society, & Environment. Steve holds an A.

B. from Cornell University, an M.S. from the University of Arizona, and a Ph.D. from Columbia University all in geology. His research interests in structural geology and tectonics have taken him in the field on several continents. Steve, a Fellow of the Geological Society of America, has won the highest teaching awards at both the college and campus levels at the University of Illinois, and has also received a Neil Miner Award from the National Association of Geoscience Teachers for "exceptional contributions to the stimulation of interest in the Earth Sciences.

" In addition to research papers and Earth: Portrait of a Planet , Essentials of Geology , Earth Science , and Laboratory Manual for Introductory Geology , he has co-authored Earth Structure: An Introduction to Structural Geology and Tectonics, and Basic Methods of Structural Geology .