Geologic Map of Idaho National Recreation Area Etched on the Grand Canyon's

Etched on the Grand Canyon's steep walls are stories of how this majestic landscape came to be: stories of volcanic islands

offering adventures for all skill levels

as mapped by the UGS on 7

• Entries that include at-a-glance technical details

this map captures the diverse character of this region

Geologic Map of Idaho National Recreation Area Etched on the Grand Canyon'sThe Geologic Map of Idaho brings together the extensive mapping and associated research since the previous statewide compilation published in 1978. Over ninety geologic resources were used to compile the map (see accompanying booklet). The northern and western parts of the state were compiled by R. S. Lewis; the eastern and southeastern parts were compiled by P. K. Link and S. P. Long. The geology was initially drafted at 1: 500,000 scale, scanned,