Frosty

Geography & Climate

Frosty is located in United States, within the Aleutian Ridge Volcanic Arc of the broader North America Volcanic Regions. Situated at 55.07° N, 162.84° W in the Northern Hemisphere, the volcano lies within a subarctic climate zone. With a summit elevation of 1,728 meters above sea level, Frosty is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Frosty sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in United States near Frosty, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is andesite / basaltic andesite, 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

Frosty Peak, the youngest of two large volcanic structures of the Cold Bay Volcanic Center, is the westernmost Holocene volcano on the Alaska Peninsula, SW of the village of Cold Bay. This symmetrical late-Pleistocene to Recent stratovolcano is constructed within one of two coalescing craters. The western wall of the ice-filled northern crater is breached by a large valley glacier. The symmetrical summit cone rises about 600 m above the floor of the southern crater. The oldest products of the roughly 100 km3 Cold Bay complex form the late-Pliocene to early Pleistocene Morzhovoi Volcanics at the southern end. Morzhovoi is an extensively eroded basaltic-to-andesitic stratovolcano with long U-shaped valleys extending from a central caldera. Only remnants of the volcano remain, with isolated peaks, such as North and South Walrus Peaks, that are fragments of the original caldera rim.

— Smithsonian Institution, Global Volcanism Program