Devils Garden

Geography & Climate

Devils Garden is located in United States, within the High Lava Plains Volcanic Province of the broader North America Volcanic Regions. Situated at 43.51° N, 120.86° W in the Northern Hemisphere, the volcano lies within a temperate climate zone. With a summit elevation of 1,698 meters above sea level, Devils Garden is a moderately sized peak that remains accessible to hikers and researchers for much of the year. 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

Devils Garden 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 Devils Garden 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.

GVP Reference Summary

The Devils Garden lava field, the NW-most of a group of three youthful-looking basaltic lava fields SE of Newberry volcano, east of the Cascade Range, contains 117 km2 of overlapping pahoehoe lava flows erupted from fissure vents at the NE part of the field. Inflated pahoehoe flows were erupted from spatter ramparts and spatter cones onto a nearly flat-lying surface surrounding several large kipukas of older rocks. The extremely fluid and inflated lavas left flows that typically increased from about a half meter thickness near the vent to about 5 m in more distal areas and have a volume of 1.2 km3. The flows are older than the Mazama Ash (6,800 years old) but are fresh-looking and relatively unvegetated. The precise age of Devils Garden is not known, but was considered to be either Holocene (Smith et al. 1978; Sarna-Wojciki et al. 1983) or about 20,000 years old (Chitwood 1994).

— Smithsonian Institution, Global Volcanism Program