USGS - science for a changing world

Science Topics

Maps, Imagery, and Publications Hazards Newsroom Education Jobs Partnerships Library About USGS Podcasts/RSS
Science Topics
Help
Earth material
Geologic map unit classification (Bruce R. Johnson) version 6.2: A hierarchical classification of earth materials for digital geologic maps.
Subtopics:
(none)
Alphabetical Index of Topics a b c d e f g h i j k l m n o p q r s t u v w x y z

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.usgs.gov/science//science/science.php?thcode=5&term=0
Page Contact Information: Ask USGS