vii, 78 pages : illustrations (some color) ; 28 cm + 1 color map (124 x 77 cm, folded to 26 x 22 cm).
General Note:
Shipping list no.: 2002-0219-P.
Additional Physical Form:
Also available via Internet from the USGS web site. Address as of 8/6/02: http://greenwood.cr.usgs.gov/pub/ppapers/p1644; current access is available via PURL.