Lava Flow Hazard Zones are areas designated by the United States Geological Survey for the Island of Hawaiʻi and Maui in the United States. First prepared in 1974 by Donal Mullineaux and Donald Peterson of the USGS and revised in 1992 for the Island of Hawaiʻi, the maps outline the qualitative hazard posed by lava flows based on the history of lava flow activity on each of the five volcanoes that form the Island of Hawaiʻi and Haleakalā volcano on the island of Maui. Zone 1 represents the areas that are most hazardous and Zone 9 the least hazardous.
USGS Lava Hazard Zone definitions.
The lava flow hazard zones are based on location of eruptive vents, past lava coverage, and topography.
The lava flow hazard zones on Maui use a different scale. They can be compared to Hawai'i Island's lava zones.
The USGS Hawaiian Volcano Observatory maintains an FAQ intended to answer many of the questions that arise from its maps and their various uses.
References.
 ;templatestyles src="Reflist/styles.css" / ;