Geology

US Geological Survey As an unbiased, multi-disciplinary science organization that focuses on biology, geography, geology, geospatial information, and water, we are dedicated to the timely, relevant, and impartial study of the landscape, our natural resources, and the natural hazards that threaten us. http://www.usgs.gov/ National Geologic Map Database A searchable database of lithologic and geochronologic unit names from the USGS. http://ngmdb.usgs.gov/ American Mineralogist Crystal Structure Database A searchable database of all crystal structures published in the American Mineralogist, The Canadian Mineralogist, European Journal of Mineralogy, Physics and Chemistry of Minerals, as well as selected datasets from other journals. http://rruff.geo.arizona.edu/AMS/amcsd.php Geologic Time Periods Produced by the Museum of Paleontology, University of California, Berkeley http://www.ucmp.berkeley.edu/help/timeform.html