Craters of the Moon

Geography & Climate

Craters of the Moon is located in United States, within the Yellowstone-Snake River Hotspot Volcano Group of the broader North America Volcanic Regions. Situated at 43.37° N, 113.49° W in the Northern Hemisphere, the volcano lies within a temperate climate zone. At 2,005 meters above sea level, Craters of the Moon rises above the surrounding terrain into montane or subalpine conditions. The elevation creates distinct ecological zones along its flanks, from forested lower slopes to exposed rocky terrain near the summit. The volcanic landform is characterized as a cluster, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Craters of the Moon is situated along a rift zone, where tectonic plates are pulling apart. As the crust thins and fractures, magma rises to fill the gap, creating volcanic activity. Rift volcanism typically produces more fluid lava flows rather than explosive blasts, which means communities near Craters of the Moon in United States generally face slower-moving hazards like lava flows and ground fissures rather than sudden pyroclastic events. However, rift volcanoes can still generate significant ash emissions and gas releases that affect local air quality. The dominant rock type is basalt / picro-basalt, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

Eruption History Summary

Craters of the Moon has 14 recorded eruptions in the geological database, spanning from 10060 BCE to 130 BCE. This level of eruptive frequency indicates a persistently active volcanic system that warrants ongoing monitoring.

Significance

With 14 recorded eruptions, Craters of the Moon has a substantial eruptive history that provides valuable data for understanding volcanic behavior and assessing future hazards in the North America Volcanic Regions region.

GVP Reference Summary

Craters of the Moon, the largest lava field of the Snake River Plain (SRP), covers about 1,600 km2 with more than 60 mapped lava flows erupted from eight fissure systems. About 25 cinder cones up to 250 m high formed primarily along a 45-km-long segment of the Great Rift, the principal 2-8 km wide fissure system that trends NW-SE through Craters of the Moon National Monument. Craters of the Moon lies at the NW part of the eastern SRP, with White Knob and the Pioneer Mountains along the northern boundary. The lava field was formed during eight eruptive episodes between about 15,000 and 2,000 years ago separated by quiescent periods up to about 3,000 years in duration. This contrasts with other SRP lava fields, which were formed during single eruptive episodes of relatively short duration. A complex assemblage of basaltic volcanic features is present, and cinder cones are common.

— Smithsonian Institution, Global Volcanism Program