Mode of access: Internet from the USGS web site. Address as of 11/6/07: http://pubs.usgs.gov/of/2007/1051/pdf/OF07-1051%5F508.pdf ; current access via PURL. System requirements: PC with Internet access and Adobe Acrobat Reader or similar software to handle .pdf (Portable Document Format) files.
General Note:
Relief and depth shown by shading and gradient tints. Title from HTML index page (viewed on May 22, 2007).