Hayes

Geography & Climate

Hayes is located in United States, within the Alaska Peninsula Volcanic Arc of the broader North America Volcanic Regions. Situated at 61.64° N, 152.41° W in the Northern Hemisphere, the volcano lies within a subarctic climate zone. At 3,034 meters above sea level, Hayes 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 composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Hayes 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 Hayes, 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 dacite, an intermediate to silica-rich volcanic rock. This composition typically produces more viscous magma, leading to more explosive eruptions with ash columns and pyroclastic flows. Andesitic and dacitic magmas build pressure before erupting, which is why volcanoes with this rock chemistry are often associated with Plinian-style eruptions that can send ash tens of kilometers into the atmosphere and disrupt aviation across entire regions.

Eruption History Summary

Hayes has 3 recorded eruptions in the geological database, spanning from 1850 BCE to 1200 CE. The most powerful recorded event was a paroxysmal eruption with devastating regional consequences in 1550 BCE, reaching VEI 5 on the Volcanic Explosivity Index. These eruptions span roughly 3,050 years of volcanic history.

Significance

With a maximum recorded VEI of 5, Hayes has demonstrated the capacity for paroxysmal eruptions comparable to the 1980 eruption of Mount St. Helens. Eruptions of this scale can devastate areas within 20-30 kilometers and produce ash fall that disrupts aviation and agriculture across hundreds of kilometers.

GVP Reference Summary

Hayes volcano, located in a remote and rugged part of the Alaska Range NW of Anchorage and N of Mount Gerdine, was not discovered until 1975. It was named after nearby Hayes Glacier and consists of scattered remnants of a largely snow-and-ice covered volcano that has been destroyed by catastrophic eruptions. The most widespread Holocene eruptions in the Cook Inlet area originated from Hayes between about 3800 and 3400 years ago and produced six regional tephra layers with an average volume of 2.4 km3. The latest known eruption took place about 1000 years ago.

— Smithsonian Institution, Global Volcanism Program